Health risk-benefit assessment of the commercial red mangrove crab: Implications for a cultural delicacy.

Mangrove forests, provide vital food resources and are an endangered ecosystem worldwide due to pollution and habitat destruction. A risk-benefit assessment (RBA) was performed on the red mangrove crab (Ucides occidentalis) from the threatened Guayas mangroves in Ecuador. It was aimed to assess the combined potential adverse and beneficial health impact associated with crab consumption and define a recommended safe intake (SI) to improve the diet of the Ecuadoran population while ensuring safe food intake. Target hazard quotients (THQs), benefit quotients (Qs), and benefit-risk quotients (BRQs) were calculated based on the concentrations of the analyzed contaminants (121 pesticide residues, 11 metal(loid)s, antimicrobial drugs from 3 classes) and nutrients (fatty acids, amino acids, and essential nutrients). Except for inorganic arsenic (iAs), the THQ was below 100 for all investigated contaminants, suggesting that the average crab consumer is exposed to levels that do not impose negative non-carcinogenic or carcinogenic health effects in the long and/or short term. Concentrations of iAs (average AsIII: 25.64 and AsV: 6.28 µg/kg fw) were of the highest concern because of the potential to cause negative health effects on long-term consumption. Despite the thriving aquaculture in the Guayas estuary, concentrations of residues of the antimicrobial drugs oxytetracycline (OTC), florfenicol, and nitrofurans still were low. Based on the fact that different risk reference values exist, related to different safety levels, four SI values (0.002, 0.04, 4, and 18 crabs/day) were obtained. The strictest intake values indicate a concern for current consumption habits. In conclusion, the red mangrove crab contains various important nutrients and can be part of a balanced diet for the Ecuadorian population when consumed in limited portions. The present study emphasizes the importance of safeguarding the quality of the environment as a prerequisite for procuring nutritious and safe food.

Pesticides residues in tobacco smoke: risk assessment study.

Pesticides are not only used on food but also on non-food crops, such as tobacco, to control a range of unwanted animal, plant, and microbial, fungal pests. The residue levels in tobacco leaves are expected to decline up to harvest, during drying, and when the leaves are further processed. Additional pesticides may also be applied to the finished product and residue levels may remain present even when the tobacco is burned. Human exposure to pesticide residues on tobacco occurs when residues remaining in cigarette smoke are inhaled. Based on this assumption, the objectives of this research were (i) to determine the level of pesticides residues in harvested tobacco leaves and (ii) to assess the risk of human exposure to these residues in tobacco smoke. Pesticide residues were detected in all analysed tobacco samples. These detected residues represent ten different active ingredients (AI), three of these AIs (thiodicarb, alachlor, and endosulfan) are no longer allowed in Europe. A 54.7% of these residues were quantifiable. Furthermore, it was found that with the use of solid-phase extraction sorbent (SPE) as adsorbent and n-hexane as solvent, higher recoveries of the pesticide residues in the tobacco smoke from the amount spiked can be obtained. It was also found that cigarette filters help to reduce the intake of residues of pesticides that may be present in cigarettes. Finally, the study concluded that both active smoking and passive smoking populations are exposed to pesticide residues in the tobacco smoke.

Quantification of pesticide residues in the topsoil of Belgian fruit orchards: terrestrial environmental risk assessment.

BACKGROUND: Pesticides are widely used in fruit orchards. In the context of integrated pest management (IPM) Flemish farmers are advised to restrict the use of pesticides. However, pesticide residues could still pose a threat to beneficial organisms. To date, it is not well known which residues are present in IPM orchards. This study focuses on the pesticide concentration in the topsoil and the implications for soil-dwelling organisms. RESULTS: Topsoil was sampled in ten sweet cherry (Prunus avium (L.) L.) and eight apple (Malus domestica Borkh.) orchards in Flanders (Belgium), to quantify the concentration of pesticide residues. Topsoil was selected because it is a major exposure route for beneficials. Both pesticides from both current spraying schedules and those used previously were found. In addition, an environmental risk assessment was performed using species sensitivity distribution (SSD) and toxicity/exposure ratio (TER) approaches. The SSD approach led to a more conservative outcome. None of the pesticides in the spraying schedule revealed a risk, although some of the persistent and banned pesticides may continue to do so. CONCLUSION: Spraying schedules are good predictors of environmental contamination. Monitoring of residues remains essential to determine the real residue concentration in the topsoil. SSDs proved valuable. It was inferred that in addition to the standard test with the earthworm Eisenia fetida (Savigny, 1826), an arthropod test organism such as Folsomia candida (Willem, 1902) should be used in future risk assessments because it displays higher sensitivity towards insecticides.

Cumulative probabilistic risk assessment of triazole pesticides in Belgium from 2011-2014.

Pesticide residues in food can lead to harmful toxic effects when exposed. Some of these compounds have a common Mode of Action and thus elicit a similar biological response. This paper considers the triazoles, a class of widely used fungicides exhibiting the same short-term (acute) and long-term (chronic) response in humans. We examined Belgian pesticide residue data from 2011-2014 and coupled these with the results of the Belgian food consumption survey of 2004. Cumulative probabilistic risk assessment was done using the Monte Carlo Risk Assessment 8.0 web application. The European Food Safety Authority (EFSA) published a guidance document that proposes both optimistic and pessimistic scenarios for dietary exposure assessment. Other than those two, a third, more balanced, scenario was simulated and showed an exposure right in between the EFSA scenarios. In the optimistic scenario, the foods with the highest measured residues in the residue data contributed the most to the total health risk. In the balanced and pessimistic scenarios, the highest contribution to the total health risk was made by active ingredients with a high sampling rate and/or a high consumption rate. No significant trends were observed in the health risk through 2011 to 2014, and the exposure distribution showed no health risks for the extreme consumers, with one exception in 2012.

Exposure to DDT and its metabolites from khat (Catha edulis) chewing: Consumers risk assessment from southwestern Ethiopia.

Khat (Catha edulis) is one of the most consumed plant in the horn of African countries. However, it is a stimulant plant that has several side effects on the health of consumers. On top of that, the khat leaves used for human consumption are often contain contaminants such as pesticide residues. The present study aims to investigate the level of DDT residue and its metabolites (p'p-DDE, p'p-DDD, o'p-DDT and p'p-DDT) in khat samples and to undertake exposure assessment to consumers. The khat samples were collected from local markets in southwestern Ethiopia. Consumption survey was undertaken using 24 h recall method for both male and female khat consumers. The finding showed that 80% of the khat samples contained DDT and its metabolites. Some of the residues were above the maximum residue limit (MRL) set by Food and Agricultural Organization (FAO). The concentration of p'p-DDE and p'p-DDT in khat were in the range of 0.033-0.113 and 0.010-0.026 mg/kg, respectively. High concentration of the metabolite (p'p-DDE) compared to the parent compound (p'p-DDT) revealed the historical use of DDT in the study area. Probabilistic exposure analysis indicated that the mean and 97.5 percentile (P97.5), of the estimated daily intake of total DDT were 0.002 and 0.006 mg/kg bw/day, respectively. The study concluded that khat consumers are exposed to the stimulant effect of the plant as well as DDT and its metabolites in Jimma zone.

Multi-residue determination and ecological risk assessment of pesticides in the lakes of Rwanda.

BACKGROUND: To boost agricultural productivity for both domestic and export purposes, agricultural inputs such as pesticides are being promoted in Rwanda. Even though the use of pesticides is important for agriculture, their residues eventually end up in different environmental compartments and may negatively affect the environment. The purpose of this study was to determine the level of knowledge and awareness of the smallholder farmers towards the use of pesticides in Rwanda and to evaluate the ecological risks of pesticides in the surface water and in the vertical profile of Lake Kivu. RESULTS: Based on the collected data, a method to monitor 33 currently used pesticides was developed. No contamination of the lower water layer was found, indicating that the groundwater that flows into Lake Kivu has not been polluted. Of the pesticides in the surface water, malathion exceeded the risk thresholds and posed a risk towards arthropods. CONCLUSION: The results of this study show that there is a lack of farmer's awareness towards the hazards of pesticides when working with these compounds. Farmers in Rwanda are in need of specialised stewardship for pesticide application training and guiding services. Surface water has been contaminated with malathion, metalaxyl and carbendazim which were the most used pesticides by the farmers in the environment.

Pressure of non-professional use of pesticides on operators, aquatic organisms and bees in Belgium.

Various studies focus on professional pesticide use, whereas pressure of non-professional use on human and the environment is often neglected. In this study, an attempt was made to estimate the pressure of non-professional use of pesticides on operators, aquatic organisms and bees in Belgium based on sales figures and by using three exposure models. A classification in non-professional use was made based on type of pesticide, application method and on intensity of non-professional use. Pressure of non-professional use on operators is highest for intensive operators, caused by the use of insecticides in an aerosol spray can. Pressure of non-professional pesticides on aquatic life is mainly generated by the use of herbicides. The aerosol spray induces the highest pressure whereas the trigger application hardly affects operator and environmental exposure. The ordinary non-professional user generates most pressure on aquatic organisms. Pressure of non-professional pesticides on bees is mainly caused by the use of insecticides, especially the active substance imidacloprid in combination with the aerosol spray can application method applied by an intensive operator. In general, both total usage (kg) and pressure of pesticides decreased for the period 2005 to 2012 due to efforts made by the government and industry. The results of this study suggest to pay special attention to aerosol spray applications and the non-professional use of insecticides.

New risk indicator approach for Operators, Workers, Bystanders and Residents for a sustainable use of plant protection products.

In 2009, the European Union adopted the Directive on Sustainable Use of pesticides (SUD, Directive 2009/128/EC) establishing a framework for achieving a sustainable use of Plant Protection Products (PPPs) through reducing the risks and impacts of PPP use on human health and the environment, promoting integrated pest management and stimulating effective non-chemical alternatives. The core idea of the SUD is that it is necessary to monitor the use of PPPs through the implementation of an appropriate set of risk indicators to monitor progress and trends in risk reduction within the Member States. To contribute to this direction, following a comprehensive analysis of the risk (including procedures of risk assessment and risk management) and involving stakeholders in the decision process, specific toolboxes of practical indirect risk indicators of exposure of Operators, Workers, Bystanders and Residents were developed and are now available to be used by Member States (MSs) based on their specific context.

Risk assessment of pesticide usage by farmers in Commewijne, Suriname, South America: a pilot study for the Alkmaar and Tamanredjo regions.

Limited scientific work is available on pesticide use and exposure in Suriname. Therefore, research was conducted to assess the application, safety practices (use of personal protective equipment (PPEs)), and potential risk of pesticide use by means of a face-to-face questionnaire and determination of the international estimated short-term intake (IESTI)). The amount of pesticide used was compared with the label and the in the European Union (EU) authorized dose. The majority of the farmers was male between 41 and 60 years and followed a primary education only. Less than 5 % of farmers used non-authorized pesticides. Results showed that most farmers (58 up to 100 %) apply a dose, which is within 0-100 % of the regulated dose (label and EU). Good results were obtained for the use of most PPEs. Statistical analysis did not reveal a significant difference between the different age classes, the different levels of education, and the use of PPEs. Pesticide residue analysis of four major crops showed that 22 % of the samples contained pesticides (13 % imidacloprid and 9 % chlorothalonil). The results for imidacloprid were higher than their respective maximum residue levels (MRLs) and were used for calculation of the IESTI. The highest observed IESTI value was 74.5 % of the EU acute reference dose (ARfD), giving rise to concern about pesticide usage. In Suriname, educational programs, good agricultural practices (GAP) training, sustainable agricultural practices, food monitoring studies, and legislative control mechanisms are urgently needed to protect farmer's health and the environment and to ensure food safety.

Stakeholder attitudes towards cumulative and aggregate exposure assessment of pesticides.

This study evaluates the attitudes and perspectives of different stakeholder groups (agricultural producers, pesticide manufacturers, trading companies, retailers, regulators, food safety authorities, scientists and NGOs) towards the concepts of cumulative and aggregate exposure assessment of pesticides by means of qualitative in-depth interviews (n = 15) and a quantitative stakeholder survey (n = 65). The stakeholders involved generally agreed that the use of chemical pesticides is needed, primarily for meeting the need of feeding the growing world population, while clearly acknowledging the problematic nature of human exposure to pesticide residues. Current monitoring was generally perceived to be adequate, but the timeliness and consistency of monitoring practices across countries were questioned. The concept of cumulative exposure assessment was better understood by stakeholders than the concept of aggregate exposure assessment. Identified pitfalls were data availability, data limitations, sources and ways of dealing with uncertainties, as well as information and training needs. Regulators and food safety authorities were perceived as the stakeholder groups for whom cumulative and aggregate pesticide exposure assessment methods and tools would be most useful and acceptable. Insights obtained from this exploratory study have been integrated in the development of targeted and stakeholder-tailored dissemination and training programmes that were implemented within the EU-FP7 project ACROPOLIS.

Exposure and health risk assessment of applicators to DDT during indoor residual spraying in malaria vector control program.

We assessed exposure of applicators, health risk of DDT to the applicators and evaluated the applicability of existing pesticide exposure models for indoor residual spraying (IRS). Patch sampling for dermal and personal air sampler for inhalation exposure were used in monitoring 57 applicators on the exposure assessment to DDT. The exposure of the applicators was also estimated using three exposure models. The mean actual dermal exposure was 449 mg total DDT per applicator per one house treatment. The applicators were exposed to DDT much beyond the estimated AOEL (acceptable operator exposure level) of DDT. The exposure estimated with ConsExpo 5.0 b01 model is situated between the median and the 75th percentile of the experimental data. On the other hand, spraying model 1 and spraying model 10 overestimate the exposure. Thus, these three models cannot be directly used for the particular circumstances of IRS as a tool for risk assessment. In general, use of DDT in IRS as a control method for malaria mosquitoes holds a high health risk for the applicators. Strict implementation of spraying procedures stated in the IRS manual of World Health Organization (WHO) is necessary to reduce the exposure level and health risk of applicators to DDT.