Results Of Biological Monitoring Research Articles

Use of Biological Monitoring to Assess Health Damage from Environmental Pollution with Metals

Introduction: The government system of public health monitoring was created in order to eliminate adverse health effects of environmental factors in humans. The use of human biological specimens as markers of effect of environmental pollution makes it possible to assess the dynamics of concentrations and levels of exposure to priority metals, to identify territories with the highest and lowest levels of priority metals, and to predict both negative and positive changes in response of critical organs and systems based on trend analysis. Objective: To develop a biomonitoring algorithm to improve objectivity of assessing human health damage caused by environmental pollution with metals. Materials and methods: Concentrations of metals in human biological specimens were measured by atomic absorption spectrometry. Cause-and-effect relationships were established by mathematical modeling of the relationship between the dose of exposure at its various pathways and metal concentrations in human blood, urine, hair and nail specimens. Results: We propose a biological monitoring program, which includes determination of territories of the highest potential risk of health damage causes by priority metals, of exposure zones and monitoring points spatially linked to economic entities classified as those posing extremely high and high potential human health risks, of the size of population at risk and particular risk groups, as well as substantiation of priority metals of natural and man-made origin, media and pathways of exposure based on the results of proven causal relationships in the system “exposure – marker of exposure – marker of effect”, the study and dynamic assessment priority metal concentrations in biological specimens of individuals at risk. The detection of increased levels of metals in biological specimens may indicate that the environmental pollution is dangerous to human health and requires managerial decision making as a means of managing health risks and eliminating health damage manifested by diseases associated with metal exposure. Conclusion: The suggested algorithm of biological monitoring, aimed at establishing and eliminating adverse effects of environmental factors in humans will contribute to the development of the public health monitoring system in terms of determining and specifying priority territories, zones, control points, and relevant indicators for inclusion in monitoring programs. The results of biological monitoring of metals can be included in the substantiating materials of expert opinions, used in justifying the prosecution of persons guilty of pollution of the environment with metals due to proven violations of mandatory sanitary and epidemiological requirements by economic entities that caused harm to public health, in justifying and evaluating the effectiveness of sanitary, hygienic, and preventive measures.

Assessment of the Health Status of Children Exposed to Industrial Toxicants in the Towns with Developed Non-Ferrous Metallurgy of the Sverdlovsk Region

Introduction: In the Sverdlovsk Region, the risks posed by cadmium, arsenic and lead exposures account for higher disease rates in the most sensitive groups of population. Recent studies have shown that these toxicants have an effect on mineral metabolism, damage to liver cells, kidneys, immunity indicators, and the nervous system. Objective: To assess the levels of cadmium, lead and arsenic in biological fluids of preschool children aged 3–6 years, living in towns with developed non-ferrous metallurgy, and possible changes in the health status at the detected level of toxicity. Materials and methods: The study was conducted in six towns of the Sverdlovsk Region with developed non-ferrous metallurgy. Environmental pollution in the study areas was assessed based on data of socio-hygienic monitoring. Biological monitoring was carried out to establish the levels of toxicants in blood and urine of children. A descriptive analysis of chronic morbidity in preschool children was performed, and the results of a special health examination of children (including that by a pediatrician and a neurologist) were presented. Mathematical modeling using decision trees was carried out. Results: Health monitoring data indicate an excess of the average regional prevalence rates in the studied preschoolers in nine disease categories. According to the results of an in-depth examination of the preschool children, diseases of the skin and subcutaneous tissue, diseases of the respiratory system, blood diseases and individual disorders involving the immune mechanism, and digestive diseases prevailed. Among concomitant diseases, the most prevalent were diseases of the digestive, nervous, and respiratory systems. Assessment of the neurological status showed that the largest percentage of children had residual cerebral insufficiency, attention deficit hyperactivity disorder, and cerebrastenic syndrome. Biomonitoring results indicated a higher level of lead, arsenic and cadmium in the biological fluids of those children. Mathematical modeling demonstrated statistically significant correlations between lead, cadmium, and arsenic concentrations in environmental objects, biomonitoring results, and clinical and laboratory examination data of children (the blood levels of alanine aminotransferase, zinc, total protein, phagocytic index, and the carrier of the marker of apoptosis CD95+). Conclusions: The results of biological monitoring were consistent with data on chronic morbidity in preschool children. Modeling data provided the body burden of toxicants, above which deviations of clinical and laboratory parameters from the reference values may occur. The findings can be used in implementation of targeted measures for disease prevention.

Genotoxicity Associated with 131I and 99mTc Exposure in Nuclear Medicine Staff: A Physical and Biological Monitoring Study.

Nuclear medicine staff are constantly exposed to low doses of ionizing radiation. This study investigated the level of genotoxic effects in hospital employees exposed to routinely used 131I and 99mTc in comparison with a control group. The study compared the results of physical and biological monitoring in peripheral blood lymphocytes. The effects of confounding factors, such as smoking status and physical activity, were also considered. Physical dosimetry monitoring revealed differences in the individual annual effective dose as measured by finger ring dosimeter and whole-body dosimeter between the 131I- and 99mTc-exposed groups. The DNA damage studies revealed differences between the groups in terms of excess premature chromosome condensation (PCC) fragments and tail DNA. Physical activity and smoking status differentiated the investigated groups. When assessed by the level of physical activity, the highest mean values of tail DNA were observed for the 99mTc group. When assessed by work-related physical effort, excess PCC fragments were significantly higher in the 131I group than in the control group. In the investigated groups, the tail DNA values were significantly different between non-smokers and past or current smokers, but excess PCC fragments did not significantly differ by smoking status. It is important to measure exposure to low doses of ionizing radiation and assess the potential risk from this exposure. Such investigations support the need to continue epidemiological and experimental studies to improve our understanding of the mechanisms of the health effects of radionuclides and to develop predictive models of the behavior of these complex systems in response to low-dose radiation.

Cause analysis of positive results of biological monitoring on pressure steam sterilization and research progress of intervention countermeasures

Cause analysis of positive results of biological monitoring on pressure steam sterilization and research progress of intervention countermeasures

Parental occupational exposure and congenital heart diseases in a Hungarian case\u2013control study

PurposeOur study aimed to explore the effect of parental occupational exposure to endocrine disrupting chemicals (EDCs) on the development of congenital heart diseases (CHDs) in the offspring, and to compare job-exposure matrix (JEM)-assessed and self-reported occupational exposures with each other.MethodsLive-born infants born in 2007–2008 were selected from the population-based Hungarian Case–Control Surveillance of Congenital Abnormalities Study. 577 cases with any CHDs were compared to 1731 matched controls. Parental periconceptional occupational exposure to EDCs was assessed by a JEM and by questionnaire-based self-reporting of parents. Multivariate conditional logistic regression analyses were conducted to explore associations between parental occupational exposure to EDCs and the entire spectrum of CHDs and by CHD subtypes in the offspring. Kappa statistics were also performed to determine the consistency among JEM-assessed and self-reported occupational exposure of parents.ResultsJEM-assessed paternal exposure to polychlorinated organic substances, phthalates, biphenolic compounds, and solvents were significantly associated with the entire spectrum of CHDs. Ventricular septal defects were significantly associated with paternal self-reported exposure to pesticides, while atrial septal defects were significantly associated to paternal JEM-assessed phthalate exposure. Paternal solvent exposure was significantly associated with atrial septal defects and right ventricle outflow tract obstructions. JEM-assessed and self-reported exposures to pesticides, heavy metals, and solvents exhibited poor agreement for mothers and slight agreement for fathers.ConclusionEven though parental occupational exposure to EDCs seems to have a minor impact on the occurrence of CHDs, the results of biological and environmental monitoring should be taken into consideration as well.

Evaluating Efficiency of Nutrition-based Disease Prevention in Metallurgical Industry Workers Based on the Results of Biological Monitoring

Introduction. The mining and metallurgical industries form the basis of the economy of the Murmansk Region. Working conditions at industrial enterprises, combined with extreme climatic conditions of the Arctic, pose an increased risk of occupational diseases. The purpose of the study was to investigate working conditions and occupational disease rates among industrial workers of the Murmansk Region in 2007–2017. Materials and methods. We studies socio-hygienic monitoring data on working conditions and occupational diseases in the population of the Murmansk Region in 2007-2017 provided by the Federal Center for Hygiene and Epidemiology of the Federal Service for Supervision of Consumer Rights Protection and Human Welfare, Moscow. Results. In 2008-2017, the most common occupational risk factors in the Murmansk Region included noise (25.8%), job strain (17.8%), and chemical factor (12.6%) while 39.2% of workers were exposed to a combination of occupational hazards. Over 10 years, the absolute number of workers exposed to dangerous and hazardous industrial factors decreased by 1.8 times. In the Murmansk Region, 84.3% of occupational disease cases were registered among workers of mining and metallurgical enterprises. In 2007-2017, the region experienced a significant decrease in occupational disease incidence mainly related to job cuts. The role of other factors (improvement of working conditions, health promotion) needs to be clarified; yet, it is possible to predict their positive influence on occupational morbidity in the next few years. Conclusion. To achieve a substantial decrease in occupational disease incidence rates, it is essential to keep improving comprehensive measures aimed at preserving workers’ health in the Murmansk Region.

Biological method in monitoring small rivers of the Oka River basin

The Oka basin is characterized by serious environmental problems associated with the depletion of water resources. Communities of aquatic organisms are the first to respond to negative changes in the aquatic environment, such communities are used as indicators in biological monitoring. The aim of the work was to assess the ecological state of the small river of the Oka basin by bioindication. The quality of the water in the reservoir was assessed by chemical indicators - biogenic and technogenic elements. The saprobity index of the reservoir was determined by the species diversity of periphyton. The results revealed technogenic and organic pollution of the small river. According to the results of biological monitoring, the value of the saprobity index is 2.85, which corresponds to class 4 of the reservoir quality, and the water is assessed as polluted. Monitoring the degree of pollution of the small river by the biodiversity of the periphyton community allows you to determine the degree of water pollution quickly.

Exposure duration and absorbed dose assessment in pesticide-exposed agricultural workers: Implications for risk assessment and modeling.

Absorbed dose assessment from dermal exposure involves multiplying skin contamination by the dermal absorption coefficient, which is usually defined for the standard workday of 8 h. This strategy may suffer from limitations when the duration of exposure is extremely variable, such as in agricultural exposure to pesticides. The aim of this study was to estimate the dose of mancozeb absorbed by agricultural pesticide applicators in a typical working day considering the real duration of exposure, to compare these estimates with those coming from the use of the Fixed Fractional Approach, and to assess the suitability of the dose estimates in the interpretation of biological monitoring results. In a series of real-life field studies on 29 workers applying mancozeb in vineyards for 38 work days, three sets of data were collected: information regarding work activities for each work day, potential (on clothes) and actual skin exposure using the "patch" methodology, and excretion of ethylenethiourea (ETU) in the 24-h pre-exposure and 24-h post-exposure urine samples. The statistical analyses were done using the R Language and Environment for Statistical Computing. Accounting for the duration of exposure led to a substantial reduction in the absorbed dose estimates, compared to the estimates coming from the Fixed Fractional Approach. In particular, absorbed dose by the body, hands' and total absorbed dose were reduced by 50%, 81%, and 80% respectively. The body dose estimated considering both approaches still correlated better with post-exposure 24-h urine ETU levels than the hands' dose, although more than 90% of the estimated total absorbed dose comes from the hands. An accurate estimate of the absorbed dose, carried out considering the real duration of exposure, can result in a higher correlation with a biomarker of occupational exposure, such as urine ETU, or at least yield more accurate results. This can facilitate the interpretation of biological monitoring data in pesticide-exposed agricultural workers despite the absence of biological exposure limits. ETU should be evaluated as a potentially relevant source of exposure due to ethylenebisdithiocarbamates' (EBDCs) degradation in the formulated product or spray mixture.

Pulmonary Function Impairment From Exposure to Mixed Organic Solvents in Male Shipyard Painters.

This study aimed to examine the effects of chronic exposure to organic solvents on lung function in a shipyard painters. Male workers in the shipyard painting department were selected as the organic solvents exposure group. Exposure was classified according to the type of work usually performed, and the cumulative exposure index was obtained using the results of biological monitoring. These were then used to divide the exposure group into low-exposure and high-exposure groups, and the dose-response relationships were examined for decreased lung function. For ventilation indices, we obtained the forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), the FEV1/FVC ratio, and the maximal mid-expiratory flow (MMF) from the forced expiratory flow-volume curve and also calculated these as percentages of the predicted values. FVC and FEV1 showed no significant differences among the control, and low-exposure and high-exposure groups, but FEV1 as a percentage of its predicted value (%FEV1) decreased with increasing exposure at 90.0%, 90.9%, and 90.0% in the control, low-exposure, and high-exposure groups, respectively. MMF% predicted also decreased significantly at 98.5%, 90.1%, and 88.4% in the control, low-exposure, and high-exposure group, respectively, indicating that workers exposed to organic solvents showed obstructive respiratory disease. Exposure to organic solvents is associated with obstructive pulmonary dysfunction rather than restrictive pulmonary dysfunction.

РЕЗУЛЬТАТЫ МНОГОЛЕТНЕГО БИОЛОГИЧЕСКОГО МОНИТОРИНГА В ЦИМЛЯНСКОМ ВОДОХРАНИЛИЩЕ В РАЙОНЕ ПРОДУВКИ ВОДОЕМА-ОХЛАДИТЕЛЯ РОСТОВСКОЙ АЭС

РЕЗУЛЬТАТЫ МНОГОЛЕТНЕГО БИОЛОГИЧЕСКОГО МОНИТОРИНГА В ЦИМЛЯНСКОМ ВОДОХРАНИЛИЩЕ В РАЙОНЕ ПРОДУВКИ ВОДОЕМА-ОХЛАДИТЕЛЯ РОСТОВСКОЙ АЭС

Increased intima-media thickness in rayon workers after long-term exposure to carbon disulfide.

Long-term exposure to carbon disulfide (CS2) is associated with increased cardiovascular mortality. However, previous studies on actual vascular changes showed heterogeneous results. Intima-media thickness of the carotid arteries (IMT) represents an established marker of atherosclerosis and a reasonable surrogate marker for cardiovascular risk. IMT was examined in a large cohort of CS2 exposed workers and the association with cumulative CS2 exposure analysed. In a cross-sectional examination, 290 exposed and 137 non-exposed workers in a German rayon-manufacturing plant were assessed. Individual cumulative exposure was calculated from this assessment combined with the results of two cross-sectional studies in 1992 and 1999 and department-specific annual means of ambient (CECS2) and individual biological (CETTCA) monitoring results obtained 1992-2009. Furthermore, cumulative duration of working in CS2-exposed departments (CEYEARS) was calculated. Examination included assessment of a broad set of known cardiovascular risk factors and IMT measurement of the carotid arteries on both sides. Multiple linear regression analyses were performed with IMT as outcome and three variants of cumulative exposure (duration of exposure, cumulative CS2, and cumulative TTCA) as well as categorised maximum CS2 exposure, all adjusted for cardiovascular risk factors. All models of cumulative exposure showed a significant increase in IMT in the group with the highest level of exposure: CEYEARS > 20 years, β = 0.045 mm; CECS2 > 270 ppm × years, β = 0.052 mm; CETTCA > 33 mg/g creatinine × years, β = 0.038 mm. Alternatively, addressing maximum exposure, workers with CS2 exposure of >10 ppm in at least 3 years exhibited a significant IMT increase (β = 0.068 mm). Long-term CS2 exposure is an independent risk factor concerning IMT changes. The amount of IMT increase, in a similar range as that associated with other cardiovascular risk factors, might be clinically relevant.

Cyphenothrin Flea and Tick Squeeze-On for Dogs: Evaluation of Potential Health Risks Based on the Results of Observational Biological Monitoring

An observational biomonitoring study was conducted involving adults and children in households that purchased and applied a cyphenothrin-containing spot-on product for dogs as part of their normal pet care practices. The 3- to 6-yr-old children had greater exposure than the adult applicators in the same house, 3.8 and 0.6 μg/kg body weight, respectively. The mean measured values in children were 13-fold lower than those estimated using the U.S. Environmental Protection Agency (EPA) current standard operating procedures (SOP) for pet products (assuming 5% dermal absorption), although the maximum absorbed dosage of one child on one day was equivalent to the default value derived from the SOPs. With regard to potential human health risks, it can be concluded that despite the inherent conservatism in both the exposure and toxicology data, the margins of exposure (MOE) were consistently greater than 100 for average, 95th percentile, and maximum exposures. More specifically, the results of this study demonstrated that the MOE were consistently greater than 1,000 for mean exposures and exceeded 100 for 95th percentile and maximum measured exposures, which clearly indicates a reasonable certainty of no harm when using the cyphenothrin spot-on products. It is also noteworthy that Sergeant’s spot-on products containing cyphenothrin currently sold in the United States have lower weight percentages of active ingredient and lower applied amounts than those used by all but two of the participant households in this study.

Construction and application of electronic sterilization quality control chain in disinfection supply center

Objective To improve the quality of pressure steam sterilization, and ensure medical safety. Methods Sterilization time, temperature, pressure, and other real-time data during the process of the pressure steam sterilization were introduced into an electronic management system. The minimum threshold of eligible sterilization was set in the electronic management system in order to automatic identify the success of sterilization. An interlocking quality control chain was established. At the same time, the BD test results, key parameters of the sterilization process, chemical monitoring results, and biological monitoring results formed the quality control chain. The quality control chain actively controlled the quality of the whole process, and ensured products having been processed by qualified sterilization before distribution. Results In the past seven months, BD test was completed 636 batches. Two batches were intercepted for unqualified sterilization process, and 1 987 batches were completed sterilization. The electronic management system actively identified the unqualified sterilization process once. 224 batches of implant products including 1 106 bags were sterilized utilizing the electronic management system. 343 (31.01%) bags were released early according to the fifth kinds of chemical indicative cards in the batch monitoring package, while the rest were released according to the biological monitoring results. Conclusions The electronic management system can improve the sterilization quality, reliability, and reduce the occult threat, by the control of the key parameters of pressure steam sterilization process and the process monitoring results. Key words: Traceability system; Sterilization; Quality control; Management; Central sterile supply

Results of long-term biological monitoring of pacific salmons in the hatcheries of Kamchatsky Krai

The following biological problems of the pacific salmons cultivation in Kamchatka are considered on the base of long-term monitoring data (2001-2013): 1) dynamics of cultivated salmons abundance in the water bodies of salmon hatcheries; 2) salmon otolith marking; 3) biological state of salmon juveniles and adults; 4) epizooty in hatcheries; 5) assessment of hatcheries effectiveness and prospects of salmon cultivation in Kamchatka. Four pacific salmon species are cultivated in Kamchatka: chum salmon (~ 60-70 %), sockeye salmon (~ 25-30 %), chinook salmon (~ 2-3 %), and coho salmon (~ 2-3 %). Their total annual release from Kamchatka hatcheries is estimated as approximately 36 million juveniles on average for the period 2001-2013. Mean contribution of chinook, sockeye and coho salmons cultivated in Kamchatka to the total release of these species from all Far-Eastern hatcheries is 100 %, 95 % and 35 %, respectively, but the contribution of chum salmon does not exceed 3-5 % of its total release. Total annual return of the salmons to Kamchatka hatcheries is about 38,000 on average, so the coefficients of return are usually < 1 % that means rather poor effectiveness of the hatcheries. The highest coefficient of return (2.1 %) is reached in Malkinsky hatchery that uses local geo-thermal water for rearing of salmon juveniles. To enhance the returns, illegal fishing (poaching) should be limited as much as possible and technologies of rearing have to be enhanced. Besides, the process of otoliths marking for cultivated juveniles in hatcheries has to be strictly controlled by technical standards for better evaluation of their contribution to commercial stocks. Promising ways of salmon fishery industry development in Kamchatka are ranching, supporting of wild salmon reproduction, and regulation of traditional fishery. All these measures should minimize effects of hatchery cultivation on structure of the stocks of pacific salmons. Health surveillance for hatchery-reared juveniles has to prevent and/or reduce their mortality in case of infectious, parasitical, alimentary and others diseases.

Influence of genetic polymorphisms of styrene-metabolizing enzymes on the levels of urinary biomarkers of styrene exposure

Styrene exposure is still present in different occupational settings including manufacture of synthetic rubber, resins, polyesters and plastic. The aim of this work was to investigate the effects of polymorphic genes CYP2E1, EPHX1, GSTT1, and GSTM1 on the urinary concentrations of the styrene metabolites mandelic acid (MA), phenylglyoxylic acid (PGA) and on the concentration ratios between (MA+PGA) and urinary styrene (U-Sty) and airborne styrene (A-Sty), in 30 workers from two fiberglass-reinforced plastic manufacturing plants and 26 unexposed controls. Personal air sampling and biological monitoring results revealed that sometimes exposure levels exceeded both the threshold limit value (TLV) and the biological exposure index (BEI) suggested by the American Conference of Governmental Industrial Hygienists. A significantly reduced excretion of styrene metabolites (MA+PGA) in individuals carrying the CYP2E1*5B and CYP2E1*6 heterozygote alleles, with respect to the homozygote wild type, was observed only in the exposed group. A reduction was also detected, in the same group, in subjects carrying the slow allele EPHX1 (codon 113), through the lowering of (MA+PGA)/urinary styrene concentration ratio. In addition, the ratio between MA+PGA and the personal airborne styrene concentration appeared to be modulated by the predicted mEH activity, in the exposed group, as evidenced by univariate linear regression analysis. Our results confirm some previous hypotheses about the role of the polymorphism of genes coding for enzymes involved in the styrene detoxification pathway: this may significantly reduce the levels of excreted metabolites and therefore it must be taken into account in the interpretation of the biological monitoring results for occupational exposure.

Neurological and neurophysiological examinations of workers exposed to arsenic levels exceeding hygiene standards.

The assessment of the neurotoxic effect of arsenic (As) and its inorganic compounds is still the subject of interest due to a growing As application in a large array of technologies and the need to constantly verify the principles of prevention and technological parameters. The aim of this study was to determine the status of the nervous system (NS) in workers exposed to As at concentrations exceeding hygiene standards (Threshold Limit Values (TLV) - 10 μg/m(3), Biological Exposure Index (BEI) - 35 μg/l) and to analyze the relationship between the NS functional state, species of As in urine and As levels in the workplace air. The study group comprised 21 men (mean age: 47.43±7.59) employed in a copper smelting factory (mean duration of employment: 22.29±11.09). The control group comprised 16 men, matched by age and work shifts. Arsenic levels in the workplace air (As-A) ranged from 0.7 to 92.3 μg/m(3); (M = 25.18±28.83). The concentration of total arsenic in urine (As(tot)-U) ranged from 17.35 to 434.68 μg/l (M = 86.82±86.6). Syndrome of peripheral nervous system (PNS) was manifested by extremity fatigue (28.6%), extremity pain (33.3%) and paresthesia in the lower extremities (33.3%), as well as by neuropathy-type mini-symptoms (23.8%). Electroneurographic (ENeG) tests of peroneal nerves showed significantly decreased response amplitude with normal values of motor conduction velocity (MCV). Stimulation of sural nerves revealed a significantly slowed sensory conduction velocity (SCV) and decreased sensory potential amplitude. Neurophysiological parameters and the results of biological and environmental monitoring showed a relationship between As(tot), As(III) (trivalent arsenic), the sum of iAs (As(III)+As(V) (pentavalent arsenic))+MMA (monomethylarsonic acid) concentration in urine and As levels in the air. The results of the study demonstrate that occupational exposure to inorganic arsenic levels exceeding hygiene standards (TLV, BEI) generates disorders typical of peripheral neuropathy.

Biological monitoring guidance values for chemical incidents

Biological monitoring is a useful tool to assess occupational and environmental exposure following a wide range of chemical incidents. Guidance values are available from international organisations to help interpret the result of biological monitoring. In addition, guidance values based on the 90th percentile of biological monitoring data obtained under conditions of good exposure control may help identify lapses in control and the need for remedial action to improve controls and reduce risk. In all cases interpretation of biomonitoring results following incidents needs care and in particular reference to the time of sample collection and basis of the guidance values. Biomonitoring guidance values specifically derived for chemical incident scenarios are not available but would be of great help to interpret biological monitoring results.

Differential organotin sensitivity in two Leucozonia species from a ship traffic area in southeastern Brazil

Tributyltin exposure is the primary cause of imposex development in gastropods, making them excellent bioindicators. The present research represents the first examination of butyltin (BT) contamination in surface sediments associated with imposex in Leucozonia nassa and L. ocellata in a harbour complex area in Espírito Santo, southeastern Brazil. The objectives of this study were to evaluate the organotin pollution in the area and to assess the sensitivity of both species to BT pollution through imposex development. Specimens were collected between 2007 and 2010 and the sediments were sampled in 2007. Imposex intensity was evaluated based on the percentage of imposexed females, the relative penis length index (RPLI) and the average value of the vas deferens sequence index (VDSI). BTs were analysed using gas chromatography equipped with a pulsed flame photometric detector (PFPD). The results demonstrated the occurrence of elevated concentrations of BTs in the sediment ranging from 383.7 to 7172.9 ng Sn g−1, indicating a severe contamination of the area, which was confirmed by the biological monitoring results. Our findings also indicated that L. ocellata is a less sensitive species than L. nassa and that this differential sensitivity plays a key role in the distributions of the populations of both species in the studied area.

Daño genotóxico en trabajadores de minería artesanal expuestos al mercurio

To determine the genotoxic damage among artisanal and small-scale mining workers exposed to mercury. Observational cross-sectional study which evaluated mercury-exposed workers (n=83), whose cells were collected by mouth swab for further staining, microscopic observance, micronuclei count, and other nuclear alterations. 24-hour urine was also collected for the determination of inorganic mercury. 68.7% of participants were male, the mean age being 43 ± 12,4 years (range: 16-76). The average time of occupational exposure to mercury was 12,1 ± 6,7 years, and the contact with mercury was 4,1 ± 3,6 kg per person per day. 93% of participants failed to wear personal protection gear while handling mercury. Results of biological monitoring showed that 17% of participants had concentrations of mercury in urine higher than 2,5 µg/L, this value being the detection limit of the measurement technique used. Results of the genotoxic evaluation evidenced that 15% of people with labor exposure to mercury presented micronuclei in mouth epithelial cells, and other indicators of nuclear alteration such as nucleoplasmic bridges, gemmation and binucleation were found, which are also considered genotoxic events associated to the exposure of physical or chemical risk agents. The finding of micronuclei in mouth epithelial cells reflects genotoxic damage associated to the labor exposure of mercury used in artisanal and small-scale mining activities.

Preliminary results of biological monitoring using benthic macroinfauna of the discharge areas of Lisbon drainage basins in Tagus estuary after new developments in sanitation infrastructures

The present study focused on the use of benthic macroinfauna to assess the ecological quality status of two specific areas in the Tagus estuary (Portugal), after the improvement in the sanitation infrastructures discharging in those areas. The sampling campaigns were held in summer of 2009, 2010 and 2011 in a set of impact and control stations. Multivariate analysis was used to determine the evolution of spatial and temporal patterns in benthic macroinfauna assemblages' composition. The ecological status of these assemblages was assessed by means of taxa richness, Shannon–Wiener diversity index and AMBI and M-AMBI biotic indices. The results obtained in both study areas seemed to indicate a trend for an improvement in the ecological condition of their benthic macroinfauna assemblages over time, although a consistent pattern was not found in all the analyses performed. When benthic macroinfauna assemblages under analysis are considerably degraded, the multimetric index M-AMBI seems to be more adequate for conducting monitoring studies than the AMBI index. However, the continuation of this work is indispensable to ensure the validity of this conclusion.