Low Pesticide Use Research Articles

Economic and Environmental Assessment of Conventional Lemon Cultivation: The Case of Southeastern Spain

Spain is the world’s leading producer and exporter of fresh lemons, with production concentrated in the southeast. The significance of this region in lemon production and the impact of agriculture on the economy and environment make optimizing lemon cultivation crucial. The main production models of lemon in Southeastern Spain (conventional Fino and Verna) are established and evaluated economically and environmentally through life cycle costing (LCC) and life cycle assessment (LCA). Both models have a similar cost structure, with variable costs (94% of the total) being the most significant, particularly labor and irrigation, followed by fertilizers and pest control. The key difference is in productivity; Verna has a higher unit cost due to lower productivity. As in LCC, in LCA the contributions of the components to the impacts of the models are very similar due to the similarities in the production models. However, Fino shows lower absolute values due to higher productivity. Fertilizers are the component with the highest contributions to the impacts, specifically their manufacture. For global warming, low values were obtained: 0.063 and 0.081 kg CO2-eq·kg−1 for Fino and Verna, respectively, which may result from diverse factors: high productivity, low pesticide and machinery use, and low nitrous oxide emissions because of aridity. Additionally, a sensitivity analysis was performed on the origin of water sources and calculation methods of pesticide emissions.

Measuring air metagenomic diversity in an agricultural ecosystem

All species shed DNA during life or in death, providing an opportunity to monitor biodiversity via environmental DNA (eDNA). In recent years, combining eDNA, high-throughput sequencing technologies, bioinformatics, and increasingly complete sequence databases has promised a non-invasive and non-destructive environmental monitoring tool. Modern agricultural systems are often large monocultures and so are highly vulnerable to disease outbreaks. Pest and pathogen monitoring in agricultural ecosystems is key for efficient and early disease prevention, lower pesticide use, and better food security. Although the air is rich in biodiversity, it has the lowest DNA concentration of all environmental media and yet is the route for windborne spread of many damaging crop pathogens. Our work suggests that ecosystems can be monitored efficiently using airborne nucleic acid information. Here, we show that the airborne DNA of microbes can be recovered, shotgun sequenced, and taxonomically classified, including down to the species level. We show that by monitoring a field growing key crops we can identify the presence of agriculturally significant pathogens and quantify their changing abundance over a period of 1.5months, often correlating with weather variables. We add to the evidence that aerial eDNA can be used as a source for biomonitoring in terrestrial ecosystems, specifically highlighting agriculturally relevant species and how pathogen levels correlate with weather conditions. Our ability to detect dynamically changing levels of species and strains highlights the value of airborne eDNA in agriculture, monitoring biodiversity changes, and tracking taxa of interest.

Environmental pesticide exposure and Alzheimer's disease in southern Spain: A cross-sectional study

The intensive cultivation under plastic in southern Spain has made the agricultural model highly productive. Although strict regulations on pesticide usage exist, exposure to pesticides in the environment has been associated with an increased appearance of neurodegenerative diseases including Alzheimer's disease (AD). A cross-sectional study was performed to examine the prevalence and risk of AD related to pesticide exposure in Andalusia (Spain). We utilized the Odds Ratio statistical test to compare the prevalence rate of AD in the exposed and unexposed areas. 40,044 cases were collected from computerized hospital records between 2000 and 2021. Districts with higher pesticide use showed significantly higher prevalence rates and increased risk of developing AD, compared to those with lower pesticide use. These findings provide further evidence supporting an increased risk of AD following environmental exposure to pesticides at the level of the general population.

Fostering temporal crop diversification to reduce pesticide use

Temporal crop diversification could reduce pesticide use by increasing the proportion of crops with low pesticide use (dilution effects) or enhancing the regulation of pests, weeds and diseases (regulation effects). Here, we use the French National DEPHY Network to compare pesticide use between 16 main crops (dilution effect) and to assess whether temporal crop taxonomic and functional diversification, as implemented in commercial farms specialized in arable field crops, could explain variability in total pesticide use within 16 main crops (regulation effect). The analyses are based on 14,556 crop observations belonging to 1334 contrasted cropping systems spanning the diversity of French climatic regions. We find that cropping systems with high temporal crop diversity generally include crops with low pesticide use. For several crops, total pesticide use is reduced under higher temporal crop functional diversity, temporal crop taxonomic diversity, or both. Higher cover crop frequency increases total pesticide use through an increase in herbicide use. Further studies are required to identify crop sequences that maximize regulation and dilution effects while achieving other facets of cropping system multiperformance.

The spatio-temporal dynamics of pesticide use: a global exploratory analysis

We utilize exploratory techniques to identify patterns in pesticide use spatial and temporal dimensions. Using data on 149 countries from 1993 to 2020, we find that some countries with low pesticide use are “catching-up” slightly. From a Markov chain analysis, we also note that the distribution of pesticide use per hectare is characterized by a low inter-class mobility, more pronounced in the head and tail of the distribution. This suggests a lock-in phenomenon once “unsustainable” agricultural systems are adopted. We complement this temporal analysis by exploring the role of “proximity” between countries in the use of pesticides and its dynamics. Three definitions of proximity are considered. The first is geographical, the second and third are based on crops produced at the country level and on countries’ GDP per capita respectively. Our results suggest that countries’ economic development explains more pesticide use than their geographic proximity or their crop similarity.

Renal tubular dysfunction in greenhouse farmers exposed to pesticides unveiled by a panel of molecular biomarkers of kidney injury

Growing evidence suggests that chronic exposure to pesticides may cause adverse effects on the health of the exposed population leading to organ-specific toxicity, including kidney damage. Traditional markers used to assess renal function (glomerular filtration rate (GFR), and serum creatinine and cystatin C –Cys-C–) are inadequate to evaluate a potential subclinical renal impairment linked to occupational exposure to pesticides, since levels above the upper limit of normal only occur when renal damage is very extensive. The use of more sensitive biomarkers is therefore needed. This study investigated novel urinary biomarkers of kidney function (microalbuminuria, osteopontin (OPN), trefoil factor 3 (TFF3), β-2-microglobulin, neutrophil gelatinase-associated lipocalin (NGAL), and Cys-C), together with the aforementioned traditional serum biomarkers, to assess potential kidney damage in farmers exposed to pesticides in an intensive agriculture setting. The study population consisted of 175 greenhouse workers and 91 healthy control subjects from Almeria (Southeastern Spain), a major hub of greenhouse agriculture. Data were collected at two different time-points of the same crop season: a period with greater pesticide use (high exposure period) and another with lower pesticide use (low exposure period). Significantly higher urinary levels of OPN and TFF3 were found in greenhouse workers than in controls, and in the high pesticide exposure period compared to that of low exposure. These changes suggest a subclinical tubular damage linked to pesticide exposure. In contrast, microalbuminuria, GFR, serum creatinine and Cys-C failed to be associated with pesticide exposure, suggesting that glomerular function was spared. Increased OPN and TFF3 levels over time may suggest a gradual progression from tubular dysfunction to chronic kidney disease in the exposed population.

Tomato pests and diseases in Bangladesh and India: farmers’ management and potential economic gains from insect resistant varieties and integrated pest management

Tomato is an important crop in Bangladesh and India, contributing to livelihoods and nutrition, but it is heavily affected by pests and diseases. This study analyzes pest and disease damage and farmers’ crop protection methods and quantified the potential economic gains of alternatives to chemical pesticides. Data come from a questionnaire survey of 744 tomato-producing farmers in India (Andhra Pradesh and Karnataka) and Bangladesh (Jashore). Farmers reported an average tomato yield loss from pests and diseases of 11.0 t/ha, of which Phthorimaea absoluta caused 2.1 t/ha. Farmers relied heavily on chemical pesticides, but also applied other methods. Better knowledge of pesticide health risks and beneficial insects and more use of alternative pest control methods were associated with lower pesticide use. Using an economic surplus model, we estimate ex-ante that the promotion of integrated pest management for the control of P. absoluta could generate economic gains of USD 264 million in Bangladesh and India over a 20-year period while insect resistant varieties could generate economic gains of more than USD 8.6 billion over this period.

Diversity of pesticide use trajectories during agroecological transitions in vineyards: The case of the French DEPHY network

CONTEXTWinegrowers apply large quantities of pesticides to their vineyards to reduce high cryptogamic pressure. But these practices must change to lower pesticide use and improve viticulture sustainability. Different options for curbing pesticide use exist, and they can be progressively implemented following a specific temporal scheme in each production system. Some change trajectories can be more efficient than others in limiting pesticide applications. Combining trajectory studies and typology may be helpful in characterizing how farmers change their practices and in summarizing the various production system trajectories possible when transitioning towards pesticide use reduction. OBJECTIVEThe aims of this study were i) to identify different types of pesticide use trajectories, and ii) to understand the options implemented by winegrowers to reduce their pesticide use. METHODSWe analysed data from 161 farming systems in the DEPHY farm network in 12 French winegrowing regions over a 10-year period. Pesticide use was assessed with the treatment frequency index (TFI). We characterized the TFI trajectory of each farming system with six indicators and built a typology of TFI trajectories. We then analysed several indicators such as the use of biocontrol products and the dose sprayed to identify some of the management options chosen to achieve these pesticide use trajectories. RESULTS AND CONCLUSIONSThree clusters were identified and characterized in terms of pesticide use strategy. The first cluster represented farms with an initial point close to the regional average and which did not experience a significant TFI reduction (−13%). The second cluster comprised farms with a low TFI when entering the network that were able to further reduce their TFI over time (−48%). The last cluster represented farms with a high initial TFI and a high reduction (−63%). All clusters managed to reduce their pesticide use by combining several technical levers at different intensities. Some differences in the levers between clusters were observed. Cluster 2 farms are in the process of converting to organic farming and using the associated levers such as biocontrol and mechanical weeding. SIGNIFICANCEThe changes implemented by cluster indicate a varying degree of progress in the transition towards pesticide use reduction. The initial point was identified as having a strong influence on the end result. The more intensively the technical levers were combined, the more difficult it was to reduce pesticide use. The DEPHY network supported winegrowers in their reduction of pesticides who managed to reduce their pesticide use by 13% to 63%.

Agro-economic performance of peach orchards under low pesticide use and organic production in a cropping system experimental network in France

A significant reduction in chemical pesticide use is strongly recommended in fruit production systems to reduce environmental and consumer health risks. Our objectives were to assess the consequences of pesticide reduction use on peach orchards’ agronomic and economic performance. Three management strategies were tested at six sites in France during the 2013–2019 period within a network using the system experiment methodology: conventional reference systems (REF) representatives of current commercial orchards, low-input (LI) systems with reduced chemical use and according to Integrated Production guidelines and organic systems (ORG). The last two systems combine many action levers ranging from structural planting strategy and combined with many alternative methods carried out throughout the years to progress towards agroecological orchards. The performance indicators were statically compared to those observed in the conventional REF system growing under the same experimental conditions over seven years. Chemical pesticides were reduced by 55% in LI compared to REF systems (20.4 treatment frequency index). Marketable yield was significantly lower in LI (−13%) than in REF systems (33.0 t ha-1). The reduction in production costs per hectare in LI systems (−11.4%) did not compensate for the decrease in gross revenues (−14.2%), resulting in a significant reduction in margins (gross revenues minus production costs, −15.8%). In the ORG systems, chemical pesticides were reduced by 80% compared to REF systems. The marketable yield was strongly reduced (−68%), but economic margins were close to REF systems thanks to the premium prices. The agroecological systems achieved in a quarter (LI) and half (ORG) of the situations (system x year) a 50% reduction in chemical pesticides and similar margins to the REF system. However, the reduction of pesticides in LI and ORG systems was accompanied by increased production costs expressed per kg of fruit and the lowest yield stability. These results highlight the importance of commercial labels to promote more eco-friendly orchards considering the impact on production costs.

Important role of the government in reducing pesticide use and risk sustainably in Thailand: Current situation and recommendations.

Agriculture is an important aspect of Thailand's GDP and development. It ranks as the 8th largest exporter in the world, however, pesticide use associated with the agriculture is ranked 18th in the world and 5th in Asia. Previous studies have clearly stated that pesticides are a threat to human health and the environment. The government is now making efforts to address pesticide use and the health impacts of pesticide use, however, these efforts are still in need of completion. This paper aims to summarize: (1) the current situation with regard to pesticide use in Thailand; (2) the current situation with regard to pesticide poisoning in Thailand; and (3) important role of government in reducing pesticide use and risk sustainably in Thailand: current situation and recommendations. This article suggests that government is a significant driver for reducing pesticide use and risk sustainably and the establishment of push and pull policies, legislation, and strategies. The government needs to strictly adhere to international conventions. Introducing a pesticide tax is essential to reduce redundant pesticide use. Updating of the current act, specific regulations with regard to pesticides and strict enforcement are urgently required. Licensing pesticide applicators should be implemented continuously. Promotion of alternative pest management is needed by supportive production inputs, technology, and markets as well as the development of a monitoring and certification system. Educating consumers on how to choose safe agricultural products and reduce risk from pesticide residues in the products is also necessary. All approaches should be implemented simultaneously and instantly. Importantly, the government needs to cooperate with agricultural sectors, health and environmental sectors, private sectors, as well as food industries to tackle complicate issues in a sustainable manner and lower pesticide use and risk sustainably in Thailand.

Local management and landscape composition affect predatory mites in European wine-growing regions

Sustainable land use in agricultural landscapes is essential to counteract the global decline of biodiversity, as well to ensure ecosystem services like natural pest control. Phytoseiid mites are key natural enemies of pest mites in vineyards but how local management and landscape context affect phytoseiid mites remains poorly known. In this study, we examined the effects of farming systems, inter-row management and landscape composition on phytoseiid mite communities in 156 vineyards across five European wine-growing regions. Our results showed that phytoseiid communities were mainly dominated by one or two phytoseiid species across Europe and that local management was a major factor affecting population densities. According to the wine-growing regions, phytoseiid mite densities benefited from integrated pest management or conventional farming compared to organic farming and from spontaneous vegetation cover compared to seeded cover crops. Moreover, mite densities benefited from increasing proportions of vineyards at the landscape scale. The farming systems effects were most likely related to the positive impact of the lower pesticide use in integrated and conventional vineyards. The positive effect of spontaneous vegetation cover could be related to a better supply of nutritive pollen as food resource compared to seeded cover crops, which depends on the plant species in the inter-row. Our findings indicated accordingly that a reduced pesticide use, and inter-row management are crucial factors for promoting pest control by predatory mites in European vineyards. Moreover, the proportion of viticultural area in the landscape is a considerable factor to retain stable phytoseiid mite populations.

Plastic debris in plastic-mulched soil-a screening study from western Germany.

BackgroundAgricultural plastic mulches offer great benefits such as higher yields and lower pesticide use. Yet, plastic mulches may disintegrate over time and fragment into smaller debris. Such plastic debris is expected to remain in the field after removal of the plastic mulch and thus contributes to soil contamination with plastics.MethodTo investigate this, we collected soil samples at 0–10 cm and 10–40 cm depth from three fields covered with black mulch film for three consecutive years. Three fields without any reported plastic use served as control. Visual plastic debris > 1 cm (macroplastics) was collected from the soil surface. Mesoplastics between 2 mm and 1 cm were density separated from the sampled soil using saturated NaCl solution and analyzed by Fourier-transform infrared spectroscopy. Debris ≤ 2 mm (microplastics) was dispersed from 50 g soil using sodium hexametaphosphate solution followed by the aforementioned density separation. The separated polyethylene (PE), polypropylene (PP), and polystyrene (PS) were quantified via solvent-based pyrolysis–gas chromatography/mass spectrometry (Py–GC/MS).ResultsWith 89–206 fragments ha−1, the majority of macroplastics were located in fields previously covered with mulch films. 80% of the collected specimen were identified as black PE film. The number of mesoplastics in plastic-mulched soil was 2.3 particles kg−1, while only 1.0 particles kg−1 were found in the reference fields. Py–GC/MS revealed microplastic levels of up to 13 mg kg−1. The PE content was significantly higher in plastic-mulched fields than in reference fields.DiscussionAlthough the identified plastic levels are lower than those reported in comparable studies, our results still suggest that plastic mulching functions as a source of plastic debris in agricultural systems. Due to its severely restricted degradability, these plastics are likely to accumulate in soil in the long term and further fragment into smaller and smaller debris.

Regional Differences in Lymphomagenesis Identified through Quantification of AICDA-Mediated Subclonal Evolution in Follicular Lymphoma: Do Pesticides Play a Role?

Background:Environmental risk factors for lymphoma are ill-defined and controversial. Epidemiologic studies have demonstrated an association between pesticide exposure and an increase in non-Hodgkin lymphomas (NHL), particularly those with a 14;18 translocation. However, in the absence of a mechanistic explanation for the effects of pesticide on lymphomagenesis, the data remain correlative and subject to alternative explanations.Mutagenesis due to activation-induced cytidine deaminase (AICDA) is key to lymphomagenesis, particularly in follicular lymphoma (FL). AICDA exerts physiologic effects by creating mutations in the immunoglobulin heavy locus (IGH) for somatic hypermutation in order to produce highly specific antibodies. AICDA's off-target genomic damage creates “driver” and “passenger” mutations, which can be used to quantify the subclonal evolution of each tumor specimen. Using deep sequencing (10000-fold) with appropriate error-thresholding, our lab previously demonstrated that the number of AICDA-mediated mutations in the 5' UTR of BCL2 is linearly related to the sum of AICDA-mediated mutations at other off-target sites, implying that mutations within the 5'UTR of BCL2 can function as a surrogate marker for the genome-wide aberrant targeting (Spence, J Immunology, 2014). We have also demonstrated that the number of mutations within IGHV is unrelated to the sum of genome-wide aberrant mutations. The sequencing data can thus be used to determine the minimum number of subclonal populations within a specimen as defined by each region (BCL2 and IGHV).We hypothesized that the number of AICDA-generated subclones would differ in patients with FL living in high and low pesticide use regions, elucidating whether pesticide-associated lymphomagenesis acts through AICDA or an alternative mechanism. We sought to assess the feasibility of demonstrating a difference in extent of AICDA-mediated subclonal evolution in patients with FL residing in regions with high and low pesticide usage by quantifying AICDA-mediated subclones in the 5' UTR of BCL2 and within IGHV.Methods:Using a state-wide database of pesticide application organized by ZIP code, we identified 35 patients with FL seen at our institution in Western New York in locales with high (N=19) and low (N=16) pesticide usage and quantified AICDA-mediated subclones in the 5' UTR of BCL2 and within IGHV for these patients' FL specimens. This sample size provided 75-92% power to detect a difference in the number of subclones by pesticide usage, using a 2-sided 0.05 level Wilcoxon test, assuming an effect size of 75-80% probability of more subclones in one pesticide usage group.Results:We identified 19 patients from high pesticide use (1000+ gigaliters (GL)) and 16 from low pesticide use ZIP codes (<1000 GL). Pesticide volume use by ZIP code in the low group ranged from 10-664 GL with a median of 263 GL, and in the high group ranged from 1636 to 67,140 GL with a median of 4787 GL.Patients living in regions of high and low pesticide use were similar in terms of race and ethnicity. The proportion of women was also similar: 43% among high versus 50% among low. Mean age at diagnosis was 62 in the high versus 60 in the low group. Three patients were diagnosed at age < 45 in the high group while no one in the low group was diagnosed at age < 45.BCL2 subclone count was lower (p = 0.046) among those in high pesticide ZIP codes (median 3.0), compared with those in low pesticide ZIP codes (median 6.5). Although the median IGH subclone count was 278 among those in the high group versus 91.5 in the low group, there was insufficient evidence of an association between IGH subclone count and the level of pesticide usage (p = 0.36).Conclusions:The extent of subclonal evolution was significantly different between lymphoma specimens of patients residing in ZIP codes with high versus low pesticide usage. Our data suggest that AICDA-mediated subclonal evolution is negatively correlated with residence in a ZIP code with high pesticide use, raising the question of whether pesticides could induce lymphoma through an alternate mechanism. This observation calls for both corroboration and examination of alternative hypotheses. We demonstrate a feasible approach to assessing these questions in a larger dataset. DisclosuresPeterson: Abbott: Consultancy. Casulo: Verastem: Research Funding; BMS: Research Funding; Genentech: Research Funding; Gilead: Research Funding.

Endophytic Fungi of Tomato and Their Potential Applications for Crop Improvement

Endophytic fungi (EF) are increasingly gaining attention due to the numerous benefits many species can offer to the plant host, while reducing the application of chemicals in agriculture, thus providing advantages to human health and the environment. The growing demand for safer agrifood products and the challenge of increasing food production with a lower use of pesticides and fertilizers stimulates investigations on the use and understanding of EF. Other than direct consequences on the plant damaging agents, these microorganisms can also deliver bioactive metabolites with antimicrobial, insecticidal, or plant biostimulant activities. In tomato, EF are artificially introduced as biological control agents or naturally acquired from the surrounding environment. To date, the applications of EF to tomato has been generally limited to a restricted group of beneficial fungi. In this work, considerations are made to the effects and methods of introduction and detection of EF on tomato plants, consolidating in a review the main findings that regard pest and pathogen control, and improvement of plant performance. Moreover, a survey was undertaken of the naturally occurring constitutive endophytes present in this horticultural crop, with the aim to evaluate the potential role in the selection of new beneficial EF useful for tomato crop improvement.

Pesticide bioaccumulation in epilithic biofilms as a biomarker of agricultural activities in a representative watershed.

Brazil is one of the largest consumers of pesticides in the world. The high rainfall rate and inadequate soil use and management promote the transfer of these compounds to the aquatic system. The aim of this study was to identify and quantify pesticides present in epilithic biofilms in order to evaluate the effectiveness of this matrix as a bioindicator able to discriminate areas and periods with different inputs of pesticides. Among the 25 pesticides analyzed in the biofilms, 20 compounds were detected. The epilithic biofilms picked up pesticides independent of their polarities, even in the period of lower use. The frequency and median concentration of five herbicides (2,4-D, atrazine, desethyl-atrazine, simazine, nicosulfuron), three fungicides (carbendazim, epoxiconazole, tebuconazole), and one insecticide (imidacloprid) were highest in biofilms sampled in summer crops during the growing period. Biofilms collected in the upper region of the catchment, where genetically modified soybean and corn cultivated in a no-tillage system prevail, the highest frequency and median concentration of three herbicides (2,4-D, thifensulfuron, isoproturon), four fungicides (carbendazim, epoxiconazole, tebuconazole, metconazole), and one insecticide (imidacloprid) were observed. Despite the excessive amounts of pesticides used in the catchment, the median values of all pesticides in the epilithic biofilm were considered low. The lower diversity and concentration of pesticides observed in the autumn/winter season is representative of lower use of pesticides, barriers to pesticide transfer from soil to water, and the biofilm's resilience capacity to decompose pesticides.

Urinary levels of organophosphate pesticides and predictors of exposure in pre-school and school children living in agricultural and urban communities from south Spain

Background. Despite the widespread use of organophosphate (OP) pesticides, information on predictors of children's exposure to such pesticides is scarce.Objective. To assess exposure to OP pesticides in children 3-11 year-old living in agricultural communities and urban areas from Andalusia (Southern Spain), and to identify the main determinants of exposure.Methods. A longitudinal study was conducted in children 3-11-year-old children living in agricultural communities and urban areas from the provinces of Almeria, Granada and Huelva (Andalusia, Spain) between 2010 and 2011. Urinary levels of six dialkylphosphate (DAP) metabolites were measured by UHPLC-QqQ-MS/MS at the periods of low and high pesticide use in the agriculture (LPU and HPU, respectively). Information on sociodemographic characteristics, parental occupation, residential history, lifestyle and diet, among other relevant factors, was obtained from questionnaires administered to the mothers.Results. A total of 559 and 597 children participated in LPU and HPU periods, respectively. The proportion of urine samples below LOD was 67.4% for ΣDMs (sum of dimethyl metabolites), 77% for ΣDEs (sum of diethyl metabolites) and 58.5% for ΣDAPs (sum of total dialkylphosphate metabolites) in LPU period, and 50.4% for ΣDMs, 65.3% for ΣDEs and 43.9% for ΣDAPs in HPU period. Significantly greater urinary ΣDAP, ΣDM and ΣDE levels were observed in HPU relative to LPU period. Maternal schooling years, proximity of the house to crops or greenhouses, use of insecticides at home, spraying the garden with pesticides, storage of pesticides at home, house cleaning frequency, as well as child's frequency of bath/shower, were found to be the major predictors of urinary levels of ΣDAP. Likewise, not washing fruit and vegetables before consumption and banana consumption were also identified as determinants of the exposure levels.Conclusions. Urinary levels of metabolites of OP pesticides found in this study were relatively lower compared to similar studies. DAP levels were significantly increased in HPU period. Maternal schooling years and variables related to residential environment and home exposures were identified as the most relevant determinants of DAP metabolites. Regarding diet, banana consumption and not washing fruit before consumption were also identified as determinants of the exposure levels. This study contributes to improve our knowledge on the main sources and determinants of children exposure to OPS, and given that children are more vulnerable than adults this information is essential to reduce children exposure and protect their health.

If you plant it, they will come: quantifying attractiveness of exotic plants for winter-active flower visitors in community gardens

Urban community gardens are potentially important sites for urban pollinator conservation because of their high density, diversity of flowering plants, and low pesticide use (relative to agricultural spaces). Selective planting of attractive crop plants is a simple and cost-effective strategy for attracting flower visitors to urban green spaces, however, there is limited empirical data about which plants are most attractive. Here, we identified key plant species that were important for supporting flower visitors using a network-based approach that combined metrics of flower visitor abundance and diversity on different crop species. We included a metric of ‘popularity’ which assessed how frequently a particular plant appeared within community gardens. We also determined the impact of garden characteristics such as size, flower species richness, and flower species density on the abundance and diversity of flower visitors. Two plant species, Brassica rapa and Ocimum basilicum were identified as being particularly important species for supporting flower visitor populations. Flower species richness had a strong positive effect on both the abundance and diversity of flower visitors. We suggest that gardeners can maximise the conservation value of their gardens by planting a wide variety of flowering plants including attractive plants such as B. rapa and O. basilicum.

Environmental exposure to pesticides and risk of thyroid diseases

Occupational and environmental exposure to pesticides has been associated with thyroid dysfunction, particularly changes in circulating thyroid hormone levels (T3, T4) and thyroid stimulating hormone (TSH). This study assessed the association between environmental exposure to pesticides and the risk of developing thyroid diseases. A population-based case-control study was carried out among Spanish populations living in areas categorized as of high or low pesticide use according to agronomic criteria, which were used as surrogates for environmental exposure to pesticides. The study population consisted of 79.431 individuals diagnosed with goiter, thyrotoxicosis, hypothyroidism, and thyroiditis (according to the International Classification of Diseases, Ninth Revision) and 1.484.257 controls matched for age, sex and area of residence. Data were collected from computerized hospital records for the period 1998 to 2015. Prevalence rates and risk of having thyroid diseases were significantly higher in areas with higher pesticide use, with a 49% greater risk for hypothyroidism, 45% for thyrotoxicosis, 20% for thyroiditis and 5% for goiter. Overall, this study indicates an association between increased environmental exposure to pesticides as a result of a greater agricultural use and diseases of the thyroid gland, thus supporting and extending previous evidence. This study also provides support to the methodology proposed for real-life risk simulation, thus contributing to a better understanding of the real life threat posed by exposure to multiple pesticides from different sources.

Local pesticide use intensity conditions landscape effects on biological pest control.

Complex landscapes including semi-natural habitats are expected to favour natural enemies thereby enhancing natural pest biocontrol in crops. However, when considering a large number of situations, the response of natural biocontrol to landscape properties is globally inconsistent, a possible explanation being that local agricultural practices counteract landscape effects. In this study, along a crossed gradient of pesticide use intensity and landscape simplification, we analysed the interactive effects of landscape characteristics and local pesticide use intensity on natural biocontrol. During 3 years, using a set of sentinel prey (weed seeds, aphids and Lepidoptera eggs), biocontrol was estimated in 80 commercial fields located in four contrasted regions in France. For all types of prey excepted weed seeds, the predation rate was influenced by interactions between landscape characteristics and local pesticide use intensity. Proportion of meadow and length of interface between woods and crops had a positive effect on biocontrol of aphids where local pesticide use intensity was low but had a negative effect elsewhere. Moreover, the landscape proportion of suitable habitats for crop pests decreased the predation of sentinel prey, irrespectively of the local pesticide use intensity for weed seeds, but only in fields with low pesticide use for Lepidoptera eggs. These results show that high local pesticide use can counteract the positive expected effects of semi-natural habitats, but also that the necessary pesticide use reduction should be associated with semi-natural habitat enhancement to guarantee an effective natural biocontrol.

Thyroid and reproductive hormones in relation to pesticide use in an agricultural population in Southern Brazil

This study aimed to assess the association of short- and long-term exposure to pesticides with circulating levels of thyroid and reproductive hormones in an agricultural population in the South of Brazil. Serum specimens from 122 male and female adults residing in small agricultural properties were sampled both in the low and high pesticide use season. A comprehensive questionnaire was used to collect detailed information on recent and cumulative lifetime use of pesticides and other agricultural-related exposures. The difference in serum hormone levels between seasons was assessed by the T-test and Wilcoxon test for paired samples, and associations between pesticide exposure-related variables and hormone values were explored by multivariate linear regression analysis. Levels of total thyroxine (T4) and male testosterone were significantly reduced from the low to high pesticide use season. In the high exposure season, recent use of dithiocarbamate fungicides, not using full personal protection equipment, and use of manual equipment was associated with reduced levels of thyroid-stimulating hormone (TSH). Moreover, recent use of lambda-cyhalothrin (pyrethroid) was associated with reduced total T4 and increased male luteinizing hormone (LH), use of paraquat (herbicide) with reduced free triiodothyronine (T3), and use of phthalamide (fungicide) with increased male LH. We also found associations of lifetime years of agricultural work with reduced total T4 and increased male testosterone; and of lifetime agricultural work and use of various pesticide classes (i.e. insecticides, herbicides, organophosphate insecticides, dithiocarbamate fungicides, and pyrethroids), mancozeb (fungicide), and paraquat with slight changes in free or total levels of T4 and/or T3. Findings suggest that both short- and long-term exposure to agricultural pesticides may alter thyroid hormones and male testosterone levels among farm residents.