Knowledge and awareness of health effects related to the use of mercury in artisanal and small-scale gold mining in Suriname.

BACKGROUND: The use of mercury in artisanal and small-scale gold mining has negative effects on human health and the environment. In Suriname, the current gold rush resulted in estimated mercury emissions up to 63t per year. To reduce the use of mercury and the subsequent health impact to gold miners and local inhabitants, knowledge and awareness in the community should be increased. METHODS: This study evaluated the effects of a health education programme (HEP) on the levels of knowledge and awareness among local inhabitants and small-scale gold miners in active gold mining areas in the interior of Suriname, South-America. Baseline knowledge levels were assessed with a survey prior to the implementation of the HEP. Thereafter, the exact same questions were asked to evaluate the effects. A total of 959 local inhabitants and 140 gold miners completed the survey including five topics: general knowledge on mercury, potential routes of exposure, health risks for children versus adults, mercury related health effects, and reproductive risks. Additionally, participants were asked in a separate survey (n = 107) about potential exposure reduction techniques and their willingness to be involved in a future human biomonitoring programme. RESULTS: The HEP influenced knowledge on exposure routes of mercury (increase from 64% to 78% of respondents who could name the relevant exposure routes) and on health effects attributed to mercury (increase from 48% to 70% of respondents who were able to list the correct health effects). After the HEP, 70% of the respondents affirmed the higher sensitivity of children, while knowledge on reproductive health effects increased from 39% to 63%. Self-estimated levels of knowledge also increased, indicating lower anxiety regarding potential risks of mercury. Gold miners reported to be willing to improve their work procedures (e.g. burning amalgam with a retort), although suitable tools were not always available. Consistent results were found for individuals included in both surveys, before and after the health education programme. Almost all respondents in the separate survey reported to be willing to give consent for participation in a future human biomonitoring programme, for themselves and their children. CONCLUSION: The implementation of a health education programme within an existing local healthcare structure proved effective and levels of knowledge and awareness improved. Most improved was the knowledge on health effects attributable to mercury, more specifically reproductive health effects.

Evaluation of three physiologically based pharmacokinetic (PBPK) modeling tools for emergency risk assessment after acute dichloromethane exposure.

INTRODUCTION: Physiologically based pharmacokinetic (PBPK) models may be useful in emergency risk assessment, after acute exposure to chemicals, such as dichloromethane (DCM). We evaluated the applicability of three PBPK models for human risk assessment following a single exposure to DCM: one model is specifically developed for DCM (Bos) and the two others are semi-generic ones (Mumtaz and Jongeneelen). MATERIALS AND METHODS: We assessed the accuracy of the models' predictions by simulating exposure data from a previous healthy volunteer study, in which six subjects had been exposed to DCM for 1h. The time-course of both the blood DCM concentration and percentage of carboxyhemoglobin (HbCO) were simulated. RESULTS: With all models, the shape of the simulated time course resembled the shape of the experimental data. For the end of the exposure, the predicted DCM blood concentration ranged between 1.52-4.19mg/L with the Bos model, 1.42-4.04mg/L with the Mumtaz model, and 1.81-4.31mg/L with the Jongeneelen model compared to 0.27-5.44mg/L in the experimental data. % HbCO could be predicted only with the Bos model. The maximum predicted % HbCO ranged between 3.1 and 4.2% compared to 0.4-2.3% in the experimental data. The % HbCO predictions were more in line with the experimental data after adjustment of the Bos model for the endogenous HbCO levels. CONCLUSIONS: The Bos Mumtaz and Jongeneelen PBPK models were able to simulate experimental DCM blood concentrations reasonably well. The Bos model appears to be useful for calculating HbCO concentrations in emergency risk assessment.

Review of acute chemical incidents as a first step in evaluating the usefulness of physiologically based pharmacokinetic models in such incidents.

CONTEXT. Acute chemical incidents can have substantial public health consequences in terms of morbidity and mortality. OBJECTIVE. We aimed to characterize acute chemical incidents and near-misses in the Netherlands and compare the results with previous studies. This review is a first step in evaluating whether Physiologically Based Pharmacokinetic (PBPK) models can be of value in acute chemical incidents. MATERIAL AND METHODS. Government, regional, municipal and University Hospital Institutes involved in the management of acute chemical incidents in the Netherlands were contacted, and they provided data between 2008 and 2010 on the characteristics and consequences of the incidents. The study is a retrospective epidemiological study based on data from five institutes. Incidents involving biological agents or radiation were excluded. RESULTS. A total of 764 reports were available which involved 722 incidents after cross-matching the different sources of data. Forty incidents were excluded, leaving 682 incidents for which information was available in accordance with the inclusion criteria. Of the 682 incidents included in this study, most occurred in non-industrial buildings (37%) or industrial sites (34%). The most frequently observed event types were loss of containment (60%) and fire (36%), leading to gas emission (54%), followed by spill of liquid or solid chemicals (36%). The chemicals involved were most often products of combustion (e.g. smoke, soot, particles, 25%) and volatile organic compounds (e.g. solvents, styrene, xylene, 23%), followed by inorganic gases (e.g. carbon monoxide, hydrogen, hydrogen sulphide, 13%). A minimum of 847 people experienced adverse health effects following exposure during a chemical incident, and 10 fatalities were reported. The most frequently reported symptoms were respiratory (27%), due to irritant chemicals. The number of incidents related to fire and the number of injured people were higher in this study than in previous studies; 49% of the injured were transported to hospital. DISCUSSION. This study helps to identify which chemicals are frequently involved in acute chemical incidents in the Netherlands. The results will be used in future to assess whether PBPK models may be useful for risk assessment of chemicals often involved in acute chemical incidents and for which human toxicological and kinetic data are scarce.