Exposure Values Research Articles

Health check-up of a freshwater bivalve exposed to lithium.

Lithium (Li) has become essential for energy and digital transitions, especially as a component of rechargeable batteries. Its growing uses worldwide lead to increasing anthropogenic releases of Li into the environment, which is making Li as an emerging contaminant. It is thus critical to evaluate the ecotoxicological impact of Li, which has been poorly studied unlike its human toxicology. The objectives of this work were to assess the potential adverse effects of Li on aquatic ecosystems. Bioaccumulation and potential sublethal effects (at individual and cellular levels) of Li have been investigated in the widespread and ecologically relevant freshwater bivalve Dreissena polymorpha. To tackle these issues, mussels were exposed to several spiking of 40, 100 and 250μg Li L-1 for 28 days to reproduce anthropogenic contamination scenario. Results demonstrated that bivalves significantly accumulated Li in a dose-dependent manner, from 2 to 10μgg-1 dry weight (bioaccumulation factor, BAF≈19Lkg-1). Bioaccumulation of Li reached a steady-state from seven days of exposure and BAF values were constant regardless the exposure concentration indicating a tight regulation of Li body burden. Lithium exposure leads to increased energy demand associated with a higher lactate dehydrogenase activity and the decrease of protein concentrations. The observed weight gain, increased cellular metabolism, decreased apoptosis, induction of antioxidant defenses and cation content modification in D. polymorpha were also reported in previous studies on humans. The observed effects intensified with exposure concentration and duration, which implies an increased risk for aquatic organisms exposed to Li chronic contamination. Overall, the present study provides new knowledge concerning the impact of Li on non-targeted species, which have implications for the environmental risk assessment of Li in freshwater ecosystems. It also open new perspectives for the understanding of Li toxicokinetics and toxicodynamics on freshwater organisms.

Polycyclic Aromatic Compounds in Ambient PM2.5 in the Central Region of Ghana: Molecular Distribution, Origin and Cancer Risk Assessment

The distribution, sources and the cancer risk of human exposure to PM2.5-bound polycyclic aromatic hydrocarbons (PAHs) were investigated in this work. Airborne particulate samples were obtained at the Winneba highway junction (WHJ) and Apam fish-smoking community (AFC) in the Central Region of Ghana from July 2022 to June 2023. PM2.5 particulates were collected using a Gent sampler equipped with a Gast pump and a stacked filter unit. 24-hour sampling was done two times a month using Teflon filters. Dichloromethane and gas chromatography with a mass spectrometer (GC-MS) were used to extract and analyse the samples, respectively, to identify 14 PAH compounds. The study discovered average PAH concentrations of 67.38 ng/m3 at WHJ and 41.59 ng/m3 at AFC. PAH profile was predominated with Phenanthrene, accounting for 25-27 % of total PAHs. The distribution pattern of PAHs was LMW>HMW>MMW at the two research sites. A strong correlation was found among BaA, BkF, BbF and BeP. The diagnostic ratio model revealed that PAHs stemmed from pyrogenic sources. The carcinogenic PAHs (BaP, BaA, Chr, BbF, BkF, BghiP) contributed approximately 90 % to the carcinogenic activity of total PAHs, denoting a high cancer potential of PAHs. The mean levels of BaP were about 8-10 times higher than the permissible limit of 1 ng/m3. The overall cancer risk values for exposure to PAHs via inhalation were more than 10-4, signifying high cancer risks: 11.61×10-4-21.14×10-4 for children and 19.91×10-4-36.24×10-4 for adults. Reducing PM2.5 and its health effects requires the use of clean fuel and the adoption of eco-friendly transportation.

Health risk assessment of potential heavy metals bioaccumulation in specialty crops grown in farm soils amended with dredged material.

This research examined the potential human health risk associated with heavy metal bioaccumulation in specialty crops (lettuce, tomato, carrot) grown in soils amended with dredged material (DM) from the Toledo Harbor in Ohio, USA. The specialty crops were chosen to expand the scope of the study of dredged material, especially in Northwest Ohio. Previous studies have been focused on corn and soybeans, which are the major crops planted in the area. Also, lettuce, tomato, and carrot are more prominent in most garden farms in the Northwest Ohio area. The research objective was to determine the expected ecological risk coefficient, transfer factor, daily intake of metals, health risk index, and their implications in soil quality and human health when DM was used as a farm soil amendment. Our soil blends consisted of 100% farm soil (FS), 90% FS:10% DM, and 100% DM. The ecological risk assessment coefficient (takes into consideration the metal toxicity) indicated that Pb, As, Zn, Cr, Ni, Co, and Cu were below their respective threshold values suggesting low sensitive toxicity to organisms when exposed to the specific metal. In general, As exhibited preferential translocation into the edible biomass across all crops and treatments. We compared the consumption of As, Pb, Cd, and Cr in the specialty crops to published reference and background values, and the results indicated that the potential consumptions is below these values. The health risk indices for arsenic were above the maximum exposure value among all crops and treatments; however, the addition of DM decreased the risk. This study suggests that the use of the Toledo Harbor DM as farm soil amendment poses a low ecological risk and human health risk.

The Derivation of Acute and Chronic Environmental Quality Standards for Nickel in European Surface Waters: A Demonstrable need to follow scientific evidence.

Environmental Quality Standards (EQS) derived under the European Water Framework Directive are legally binding and enshrined in individual European Member State Country national legislation. These EQS are derived following well-established guidance documents. In 2013, EQS for nickel were derived for freshwaters to be protective against long and short-term exposures, at 4 and 34 µg L-1, respectively. The value for long-term exposures uses chronic ecotoxicity data and accounts for bioavailability, whereas the short-term value uses acute data and does not account for bioavailability. In 2022, the European Commission revised these values as part of the on-going legislative process. Despite an increase in available data for both chronic and acute ecotoxicity endpoints, the update and development of chronic and acute Biotic Ligand Models (BLMs) published in peer-reviewed literature, and the accessibility of vastly more monitoring data (used in the European EQS derivation), the values for the nickel EQS were reduced by increasing the assessment factors, to account for increases in apparent uncertainties. The Commission's 2022 derivation failed to consider additional chronic data for more than 20 species as well as the updated and new acute and chronic BLMs. As a result, the derived nickel EQS is limited in its applicability and relevance to European freshwater ecosystems, as illustrated in practice by the observation that monitoring sites can comply with the chronic EQS but fail the acute EQS. Here, we provide an explanation as to why this has occurred and detail what it means for the risk assessment of nickel in European Member State freshwaters. Finally, we outline a path forward, that should be relevant for any risk-based and evidence-driven regulatory framework and acknowledging that political decisions are part of the process, but that these should be separate and after scientific aspects are undertaken.

Determining the cosmetics usage patterns of consumers for exposure assessment in China.

Accurately understanding the usage patterns of cosmetics is crucial for realistic exposure assessment. However, reference values for consumer exposure to cosmetics in China have yet to be established. A continuous survey was conducted in Guangdong Province to address this deficiency. Among 1320 potential participants, 268 men and 412 women completed the survey. The survey used a weighing method to accurately obtain the actual usage amounts of cosmetics by consumers, along with photographic documentation to ensure the accuracy and completeness of the information. Based on the participants' cosmetic usage, exposure factors for a total of 20 types of cosmetics were obtained. More than 60% of the participants reported the use of shower gel and shampoo. Face cleanser, shower gel, shampoo and conditioner were used at least once a day by ∼50% of the population. The amount of use of different cosmetics varies significantly due to individual usage habits. These data hold enlightening significance for initiating a nationwide survey on cosmetic exposure levels across China.

Departing from standard practices: Strategic application of value engineering in the anatomy laboratory to enhance formaldehyde extraction using high-impact, low-cost, and low-maintenance solutions.

This study describes the process of developing a high-impact, low-cost, and low-maintenance air ventilation system for anatomy facilities. It employed the strategic application of Value Engineering (VE), assuring that the air ventilation system meets contemporary threshold limit values (TLVs) for formaldehyde in the working zone of dissection tables. A creative-innovative construction methodology was used, combining the Theory of Inventive Problem Solving (TRIZ/TIPS) and VE for an anatomy laboratory air ventilation concept. The TRIZ/TIPS aimed to resolve conflicts that impeded progress toward higher ideality, while VE aimed to develop alternative approaches to fulfill required functions at a minimal cost. The findings were first trialed in a mockup while dissecting human tissues embalmed with two protocols. The experimental results were validated by computational fluid dynamics simulations, and then followed by a pilot and commissioning phase once the physical installation of the dissection laboratory concluded. The findings demonstrate the superiority of the combined TRIZ/TIPS and VE approach in terms of air distribution and efficient formaldehyde extraction within the breathing zone. A formaldehyde exposition below 0.1 ppm, lowered air exchange rates, and system usability proved that the given third-generation ventilation system complies with contemporary TLVs and potential changes in user requirements. The third-generation ventilation system offers a cost-effective, high-impact, and low-maintenance solution for state-of-the-art air ventilation systems in the anatomy dissection laboratory. The underlying design approach ensured that formaldehyde levels in the laboratory meet the TLV and indoor air guideline values for formaldehyde exposure, at which current knowledge indicates no increased risk of cancer.

Deep learning reveals diverging effects of altitude on aging.

Aging is influenced by a complex interplay of multifarious factors, including an individual's genetics, environment, and lifestyle. Notably, high altitude may impact aging and age-related diseases through exposures such as hypoxia and ultraviolet(UV) radiation. To investigate this, we mined risk exposure data (summary exposure value), disease burden data (disability-adjusted life years (DALYs)), and death rates and life expectancy from the Global Health Data Exchange (GHDx) andNational Data Management Center for Health of Ethiopiafor each subnational region of Ethiopia, a country with considerable differences in the living altitude. We conducted a cross-sectional clinical trial involving 227 highland and 202 lowland dwellers from the Tigray region in Northern Ethiopia to gain a general insight into the biological aging at high altitudes. Notably, we observed significantly lower risk exposure rates and a reduced disease burden as well as increased life expectancy by lower mortality rates in higher-altitude regions of Ethiopia. When assessing biological aging using facial photographs, we found a faster rate of aging with increasing elevation, likely due to greater UV exposure. Conversely, analysis of nuclear morphologies of peripheral blood mononuclear cells(PBMCs) in blood smears with five different senescence predictors revealed a significant decrease in DNA damage-induced senescence in both monocytes and lymphocytes with increasing elevation. Overall, our findings suggest that disease and DNA damage-induced senescence decreases with altitude in agreement with the idea that oxidative stress may drive aging.

Disrupting and dismantling notions of preschool: exploring pre-service teachers perspectives on a study abroad

ABSTRACT Preservice teachers often carry perceptions and preconceptions shaped by their own educational journeys (Lortie, 1975). In the United States, where educational practices commonly prioritize meeting objectives and employing traditional classroom methods, these pre-existing notions influence their approach to teaching. This qualitative case study focused on six preservice teachers, exploring their perspectives and experiences during a brief study abroad in Finland and Sweden. Kolb’s Experiential Learning Theory and Mezirow’s Transformative Learning Theory framed the study, examining data derived from preservice teachers’ reflections, observations, and coursework. The findings illuminated four primary insights gleaned by the participants: a newfound appreciation for viewing children as valuable members of society, an emphasis on the significance of STEM education and environmental stewardship, a heightened awareness of equity and inclusion, and the daunting challenge of effecting positive change in education. This study highlighted the dissonance experienced by students when comparing US and Scandinavian pedagogical approaches and considering potential applications of overseas practices within the US educational context. Additionally, it identified key barriers to US implementation such as accountability demands, parental expectations, and administrative constraints. The research underscores the importance of contextualized learning experiences for preservice teachers, emphasizing the value of exposure to diverse educational systems in shaping their pedagogical perspectives and practices.

Dust exposure and its health implications to miners in Mererani artisanal and small-scale mining industry

ABSTRACT This study aimed to identify and quantify the total dust exposure to underground miners in Mererani, Tanzania, and its composition to generate evidence for informed decision- and policy-making. The Analytical Air Monitoring System (AMS) was used for dust collection, and analysis was conducted gravimetrically. The dust composition was analysed using Inductively Coupled Plasma Optical Emission Spectroscopy. The results showed significant variation in dust exposure levels across different mining zones, with miners inhaling up to 1859 mg of dust over an 8-hour period in drilling zones (DZ), 797 mg in loading zones (LZ), and 382 mg in resting zones (RZ). The mean value of dust exposure was significantly different, with a p-value of <0.05. Miners had higher levels of heavy metal and silica than those from unmined sites, with chromium being the most dominant element across all samples. Cumulative exposure to dust over time is linked to long-term respiratory impairment and serious health conditions such as lung cancer. These findings highlight the need for intervention, including education on dust hazards, provision of personal protective equipment (PPE), and enforcement of safety standards to safeguard miners’ health. Addressing these issues is critical to promoting policy reforms and sustainable mining practices in Mererani and similar communities.

Delays in Blood Work and Disease Burden: A Cross-Sectional Analysis of Unmet Blood Work Need and Seven Key Health Conditions Across 21 Countries.

This study analyzes survey data across 21 countries to explore correlations between delays in blood testing and the prevalence of seven health conditions: thalassaemias, sickle cell disorders, malaria, HIV, high fasting plasma glucose, impaired kidney function, and high LDL cholesterol. We analyzed Pandemic Recovery Survey data via multivariable logistic regression to compare blood test delays between individuals with and without medical conditions, while adjusting for sociodemographic factors. We also examined the disease burden using disability-adjusted life years (DALYs) and summary exposure values (SEV) rates. Our findings indicate profound disparities, with over 60% of respondents in Egypt, Nigeria, and India reporting they have never undergone blood tests. Individuals with existing medical conditions are significantly more likely to experience delays in blood work. There is a pronounced gap in blood work accessibility, particularly in countries with high disease burdens. Findings suggest an urgent need for interventions to improve routine blood test access for high-risk populations to reduce the underdiagnosis of significant medical conditions. Prioritizing timely and accessible blood testing can serve as a step towards mitigating healthcare disparities.

Introducing internal allocation factors for assessing aggregate pesticide exposure across multiple pathways and routes.

In the health risk assessment of pesticides, methods for external exposure assessment have been well developed. However, quantifying the contribution of various exposure pathways or routes to internal dose remains challenging. This study introduced the internal allocation factor (IAF) for 319 pesticides to investigate the impact of different exposure pathways and routes on chemical distribution within the human body. The IAFs can be calculated from various exposure sources (or pathways), routes, and biological samples. Analysis of different exposure sources revealed that crop exposure generally had the lowest IAF in organs and tissues, indicating a high contribution to the internal dose. The median IAF values for crop exposure in blood, liver, lung, kidney, fat, and muscle were all around 1.05. For three exposure routes of soil pesticide, the results found that IAF values for oral and dermal exposure routes were significantly lower than those for inhalation exposure. When the pesticide concentrations in biological samples are known, IAF can be utilized to back-calculate the pesticide levels in other organs and tissues. The results show that under a single exposure route, the concentration factor varies greatly between organs or tissues due to differences in compositions of human tissues (e.g., water and lipid contents) and pesticide properties (e.g., hydrophilicity and lipophilicity).

Association between maternal folic acid and/or multivitamin supplementation time and fetal congenital heart disease: based on the China birth cohort study.

Background: A multitude of studies have presented inconsistent outcomes regarding the association between maternal folic acid (FA) and/or multivitamin (MV) supplementation and congenital heart disease (CHD) in offspring. This study aimed to estimate supplementation time and CHD based on a prospective China birth cohort study (CBCS). Methods: In the CBCS, 114,670 singleton pregnant women who had pregnancy outcomes until August 2021 and responded to the early pregnancy questionnaire were recruited. The participants were divided into three groups: no FA or MV supplementation, supplementation commencing before pregnancy, and supplementation commencing from early pregnancy. Unadjusted and adjusted logistic regression analyses were employed to calculate the odds ratio (OR) to estimate the relative risk (RR) value of CHD exposure to FA and/or MV. Additionally, the results of this study were combined with previous studies to calculate the pooled RR. Finally, stratification and sensitivity analyses, including the propensity score matching method, were conducted to identify the robustness of the association. Results: Compared with the non-supplemented group, the RRs of CHD in groups with FA and/or MV supplementation, with supplementation before pregnancy, and with supplementation from early pregnancy were 1.23 (95% confidence interval [CI]: 0.76-2.00), 1.30 (95% CI: 0.80-2.13) and 1.19 (95% CI: 0.73-1.93), all demonstrating no statistically significant difference. The pooled RR from the forest plot was 0.98 (95% CI: 0.95-1.01), which is consistent with the findings of this study. Furthermore, the results remained approximately the same in the stratification or sensitivity analyses in different datasets, including performing 1:1 or 1:2 propensity score matching. Conclusions: The present study suggests that FA or MV supplementation before or during early pregnancy may not influence the risk of offspring developing CHD.

Health risk assessment and Sobol' sensitivity analysis of power plant air pollution (SO2 and NOX): the effect of power plant fuel change.

This study aimed to evaluate the concentrations of sulfur dioxide (SO2) and nitrogen oxides (NOX) around the Qom (a province in Iran) combined cycle power plant in relation to seasonal variations and fuel type from December 2014 to May 2015. Passive sampling was used in three monitoring sites around the power plant to assess noncarcinogenic health risks associated with exposure to SO2 and NOX. Results showed the higher concentrations of NOX and SO2 in winter than in spring. The highest concentrations of NOX in winter (when power plants used gasoil) and spring (when power plants used gas fuel) were 52.70 ± 21.70/52.70 ± 13.20 and 22.10 ± 7.00 µg/m3. Similarly, the highest concentrations of SO2 in winter and spring were 5.00 ± 0.20 and 3.90 ± 0.70 µg/m3. There was a moderately significant correlation between NOx and SO2 concentrations when the power plant consumed gasoil (Spearman rho coefficient, 0.68, p < .05). A significant difference was observed between gas concentration and fuel type (p < .05). The hazard quotient values for SO2 exposure were below 1 for all age groups, whereas those for NOx were above 1 for infants and children. The hazard index for NOX was above 1, indicating an unacceptable risk to human health. Sobol' sensitivity analysis identified the inhalation rate and NOX concentration as the most significant factors determining the noncarcinogenic risks across age groups. In conclusion, the use of gasoil by power plants increases the emission of pollutants, thereby raising the health risks for residents in these regions, particularly vulnerable demographics like children. Therefore, prioritizing air quality management such as using cleaner fuels and emission control technologies in power plants as well as continuous air quality monitoring are of utmost importance.

Clinical Impact of Lipoprotein (a) and Cumulative Low-Density Lipoprotein Cholesterol Exposure on Coronary Artery Disease in Patients with Heterozygous Familial Hypercholesterolemia

Elevated lipoprotein (a) (Lp[a]), predominantly determined by genetic variability, causes atherosclerotic cardiovascular disease (ASCVD), particularly in patients with familial hypercholesterolemia (FH). We aimed to elucidate the clinical impact of Lp(a) and cumulative exposure to low-density lipoprotein cholesterol (LDL-C) on CAD in patients with FH. One hundred forty-seven patients clinically diagnosed with heterozygous familial hypercholesterolemia (HeFH) were retrospectively investigated. Patients were divided into 2 groups according to the presence of CAD. Their clinical characteristics and lipid profiles were evaluated. There were no significant differences in untreated LDL-C levels between the 2 groups (p=0.4), whereas the cumulative exposure to LDL-C and Lp(a) concentration were significantly higher in patients with CAD (11956 vs. 8824 mg-year/dL, p＜0.01; 40 vs. 14 mg/dL, p＜0.001, respectively). A receiver operating characteristic (ROC) curve analysis demonstrated that the cutoff values of Lp(a) and cumulative LDL-C exposure to predict CAD in patients with FH were 28 mg/dL (AUC 0.71) and 10600 mg-year/dL (AUC 0.77), respectively. A multivariate analysis revealed that cumulative LDL-C exposure ≥ 10600 mg-year/dL (p＜0.0001) and Lp(a) level ≥ 28 mg/dL (p＜0.001) were independent predictors of CAD. Notably, the risk of CAD remarkably increased to 85.7% with smoking, Lp(a) ≥ 28 mg/dL, and cumulative LDL-C exposure ≥ 10600 mg-year/dL (odds ratio: 46.5, 95%CI: 5.3-411.4, p＜0.001). This study demonstrated an additive effect of Lp(a) and cumulative LDL-C exposure on CAD in patients with HeFH. Interaction with traditional risk factors, particularly smoking and cumulative LDL-C exposure, enormously enhances the cardiovascular risk in this population.

Estimated long-term dietary exposure to cadmium from consumption of spinach in the United States: A probabilistic assessment.

As part of the U.S. Food and Drug Administration's (FDA's) Closer to Zero initiative, a toxicological reference value (TRV) for oral dietary exposure to Cd was established. Dietary exposure to Cd typically occurs at low levels over a pro-longed time period. With increased focus on food sources, it is necessary to refine the risk assessment process to quantify potential health risk from dietary exposure to Cd with greater precision. This study focused on dietary exposure to Cd from spinach consumption. A probabilistic method of bridging the National Health and Nutrition Examination Survey 24-hour dietary recalls and the National Eating Trends frequency data to estimate long-term (usual) spinach consumption was applied to estimate longer term (i.e., chronic) intake among the general U.S. population and young children (0-6 years). The resulting consumption distribution was combined with a database of Cd levels representative of spinach grown in the U.S. from 2014 to 2015 and 2017 to estimate long-term dietary exposure to Cd from spinach consumption. Mean dietary exposure to Cd ranged from 0.006 to 0.026μg/kg bw/day and 0.018-0.110μg/kg bw/day among the U.S. population and young children, respectively. Exposure estimates from spinach consumption alone were below the FDA TRV range.

Acrylamide exposure in workplace cafeterias: impact of consumer choices.

Eating in workplace cafeterias is a common part of the workday. While nutritional profiles of these menus are often evaluated, exposure to chemical process contaminants like acrylamide receives little attention. This study assessed acrylamide exposure from lunches in two Spanish workplace cafeterias using the duplicate diet method, considering both lower bound (LB) and upper bound (UB) scenarios. Over two weeks, 146 food items were collected from lunch menus, covering combinations of first and second courses, dessert and bread. Potato-based dishes had the highest acrylamide levels (233 μg/kg), followed by stewed lentils (150 μg/kg) and stewed salmon with vegetables (109 μg/kg), while other meals showed lower levels (16-75 μg/kg). Daily acrylamide exposure ranged between 0-1.04 μg/kg·body weight (bw)/day for women and 0-0.85 μg/kg bw/day for men. Cafeteria-1 offered varied menu combinations, allowing zero acrylamide exposure, while cafeteria-2 had less flexibility. The margin of exposure (MOE) values for neoplastic effects varied from 1221 to 165 (LB) and from 2609 to 163 (UB), suggesting potential health concern. While workplace menus generally comply with nutritional guidelines, consumer choices critically influence acrylamide exposure. Educating consumers on safer food choices and training food handlers to reduce acrylamide in meal preparation are key to mitigating health risks.

Air pollution exposure disparities across age groups in Beijing-Tianjin-Hebei region from 2010 to 2020.

Air pollution carries different disease burdens across all age groups, with the elderly and children being the most affected. Therefore, it is of practical significance to study air pollution exposure characteristics of different age groups in the context of accelerating aging in China. In this study, we used the number of people and air pollutant concentration data at the township-level scale (the smallest administrative unit in China) to calculate population-weighted PM2.5 concentration exposure (PM2.5 PWE) values of different age groups in the Beijing-Tianjin-Hebei (BTH) region, quantified the pollution exposure disparities among different groups, and analyzed the spatiotemporal changes in such differences and their driving factors. Although air quality has improved, these improvements have not been equally distributed across all age groups, leading to intensified disparities in air pollution exposure. Specifically, the elderly were exposed to lower PM2.5 concentrations in 2010 and 2020, and the working age group had the highest annual PM2.5 PWE in 2010 and the largest reduction in PM2.5 PWE between 2010 and 2020. The PM2.5 PWE of the children group was higher in 2020. The exposure disparities among groups increased in 2020 compared to 2010, and the exposure disparities and their variations were related to the administrative area, rural employment, per capita disposable income, normalized difference vegetation index, wind speed, and temperature. This study expands our understanding of air pollution exposure disparities in China and provides a scientific foundation for addressing unequal exposure disparities across different age groups in the BTH region.

From Extractables to Exposure Data: Sensitivity Analysis of Extrapolation Algorithms with Focus on USP 〈665〉.

We evaluated algorithms designed to extrapolate extractables data for predicting process equipment-related leachables (PERLs) and assessing PERL exposure in single-use systems (SUSs) and their assemblies. The robustness and sensitivity of these algorithms were tested against variations in input data, including extrapolation algorithms for both short and long contact time extractables data obtained from the standardized extractables protocol provided in USP 〈665〉. Our findings demonstrate that extrapolated data for SUS and assemblies are suitable for safety assessments. Extrapolated and aggregated data do not systematically underestimate potential PERL exposure values, provided that the extractables data originate from experiments with a higher surface area to contact liquid volume ratio and/or a low liquid to material volume ratio compared to the use scenario. The algorithms are non-sensitive to deviations in input data, as these deviations are propagated decreasingly into extrapolated data and parameters. The quality and significance of PERL exposure calculations can be enhanced by incorporating extractables study data from experiments using a semipolar organic solution, such as ethanol.

Socioeconomic inequality in exposure to second-hand smoke among middle-aged adults of the RaNCD cohort study: a decomposition analysis

BackgroundSecondhand smoke (SHS) can cause various health problems among different age groups worldwide. Socioeconomic factors may influence the distribution of SHS exposure among population subgroups. We aimed to estimate socioeconomic inequality in SHS exposure and identify its contributing factors among a sample of Iranian adults.MethodsThis cross-sectional investigation utilized baseline data from the Ravansar Non-Communicable Disease cohort study. The study population comprised 7991 middle-aged adults aged between 35 and 65 years. To determine socioeconomic status (SES) principal component analysis (PCA) was used. The Wagstaff normalized concentration index (Cn) was utilized to measure the extent of socioeconomic inequality in SHS. Furthermore, decomposition analysis was performed to identify the factors contributing to the observed inequality in SHS exposure.ResultsThe prevalence of SHS exposure among men, women, and the total population was 38.23%, 47.29%, and 43.89%, respectively. The concentration index (Cn) value for SHS exposure was − 0.121 (95% confidence interval [CI]: -0.146, -0.096) in the study participants. Among men and women, the values were − 0.080 (95% CI: -0.122, -0.037) and − 0.095 (95% CI: -0.112, -0.063), respectively, indicating a higher concentration of SHS among individuals with low SES. Female sex (35.17%), socioeconomic status (31.83%), being married (-26.36%), and rural residency (22.44%) were identified as the primary factors contributing to the observed inequality in SHS exposure.ConclusionThe research findings revealed a pro-rich inequality in SHS, with a significant concentration among low-SES individuals. In terms of the main contributors to socioeconomic inequality in SHS exposure, policy interventions need to pay attention to females, individuals with low SES, and married individuals to address inequality in SHS exposure.

Health risk assessment of aflatoxin M1 exposure through traditional dairy products in Fasa, Iran.

Milk and dairy products are an important source of essential nutrients for human health. However, contamination of these foods poses a significant public health concern. In this study, risk assessment of aflatoxin M1 (AFM1) exposure associated with the consumption of traditional milk and dairy products in Fasa, Fars Province, Iran, was carried out. A total of 180 samples, comprising raw milk, boiled milk, cheese, yoghurt, as well as Doogh and Kashk, two traditional fermented milk-based products, were collected during two seasons of summer and winter and then analyzed using enzyme-linked immunosorbent assay (ELISA). The findings indicated that 85.55% of all samples were contaminated with AFM1 with the mean concentration of positive samples as 251.15 ± 71.97ng/kg (1.10-453.50ng/kg). The results also showed that in 68.88% of tested samples, the toxin concentration exceeded the limit set by the national standard of Iran and the European Union standard. Dietary exposure value calculated for the study population was 0.13ng/kg BW/day. Based on calculations resulting from risk characterization, hazard index (HI), liver cancer risk (LCR), and margin of exposure (MOE) for AFM1 were 0.67, 7.6 × 10-4, and 15,291, respectively. For yoghurt consumers, results showed a significant risk for the study population regarding non-carcinogenic and carcinogenicity hazard (HI > 1, LCR > 10-4, MOE < 10,000). Yoghurt showed the highest contribution rate for AFM1 exposure in various dairy products due to its higher consumption rates, followed by milk. Based on these results, there are needs for rigorous monitoring and control of cattle feeds to decrease the risk of contamination with aflatoxins.