Mass balance approach to assess the impact of cadmium decrease in mineral phosphate fertilizers on health risk: The case-study of French agricultural soils.

Cadmium is a ubiquitous and highly toxic contaminant that can cause serious adverse effects. The European Food Safety Authority (EFSA) and the French Agency for Food, Environmental and Occupational Health & Safety (ANSES) have shown that the risk related to food contamination by cadmium cannot be ruled out in Europe and France. Fertilizing material is one of the main sources of cadmium contamination in the food chain on which regulators can play to reduce cadmium exposure in the population. The aim of this work was to develop a mass-balance approach integrating the various environmental sources of cadmium to estimate the effects of a decrease in cadmium concentrations in crop fertilizers on dietary exposure and on the health risk. This approach led to a predictive model that can be used as a decision-making tool. Representative and protective fertilization scenarios associated with controlled cadmium levels in mineral phosphate fertilizers were simulated and converted into cadmium fluxes. Cadmium inputs from industrial mineral phosphate fertilizers were then compared with cadmium brought by the application of manure, sewage sludge and farm anaerobic digest, at the levels typical of French agricultural practices. Regardless of the fertilizer and scenario used, a flux lower than 2 g Cd.ha-1.year-1 reduces both the accumulation in soils and the transfer of cadmium in the food chain. It corresponds to a cadmium content of 20 mg.kg P2O5-1 or less in mineral phosphate fertilizers. Modelling the transfer of cadmium from the soil to consumed food made it possible to propose cadmium limits in fertilizers applied in France. In a global context of ecological transition to promote human health, this research will help risk managers and public authorities in the regulatory decision-making process for the reduction of environmental cadmium contamination and human exposure.

Extension of the sorting instructions for household plastic packaging and changes in exposure to bioaerosols at materials recovery facilities.

The aim of this study was to assess how extending the sorting instructions for plastic packaging would affect the exposure of workers working at materials recovery facility (MRF) to dust, endotoxins, fungi and bacteria, taking into consideration other factors that could have an influence on this exposure. Personal sampling was carried out at four MRFs during six sampling campaigns at each facility, both in sorting rooms and when the workers were involved in "mobile tasks" away from the rooms. The data was analysed by describing the extension of sorting instructions both using a qualitative variable (after vs before) and using data for the pots and trays recycling stream, including or excluding plastic film. Overall, before the extension of the sorting guidelines, the geometric mean of personal exposure levels in sorting rooms was 0.3mg/m(3) for dust, 27.7 EU/m(3) for endotoxins, 13,000 CFU/m(3) for fungi and 1800 CFU/m(3) for bacteria. When workers were involved in mobile tasks away from the rooms, these averages were 0.5mg/m(3), 25.7 EU/m(3), 28,000 CFU/m(3) and 5100 CFU/m(3) respectively.The application by households of instructions to include pots, trays and film with other recyclable plastic packaging led to an increase in exposure to endotoxins, fungi and bacteria at MRFs. For an increase of 0.5 kg per inhabitant per year in the pots, trays and film recycling stream, exposure in sorting rooms rose by a factor of 1.4-2.2, depending on the biological agent. Exposure during mobile tasks increased by a factor of 3.0-3.6. The age of the waste amplified the effect of the extension of sorting instructions on exposure to fungi, bacteria and endotoxins. Factors that had a significant influence on the exposure of workers to dust and/or bioaerosols included the presence of paper, newspapers and magazines in the sorted waste, the order in which incoming waste was treated and the quality of the ventilation system in the sorting rooms. The levels of exposure observed in this study highlight the need to implement appropriate preventive measures against bioaerosols at MRFs for dry waste. There are grounds to justify these preventive measures, both inside sorting rooms and for the MRF as a whole, regardless of whether the decision to extend sorting instructions for household plastic waste is adopted.

An inventory of trace elements inputs to French agricultural soils.

The inputs of ten trace elements (As, Cd, Cu, Cr, Hg, Mo, Ni, Pb, Se, Zn) to French agricultural soils have been assessed. The six main sources considered were: pesticides, mineral fertilizers, animal manure, liming materials, sludge and composts and atmospheric deposition. Data were collected to compute inputs at both national and regional (departmental) scales. The inventory methodology is based on two principles: data are traceable and easy to update. At a national scale, the inventory showed that trace elements inputs can be ranked: Zn≫Cu≫Cr>Pb>Ni>As=Mo>Se>Cd>Hg. Animal manure, mineral fertilizers and pesticides are the predominant sources of TEs. These results are globally in agreement with literature data though atmospheric deposition is shown to be lower than in more industrial countries such as China and United Kingdom where similar surveys were conducted. The inputs of trace elements vary strongly between regions in relation with agricultural activities. This inventory (and the related database) provides basis for developing and monitoring policies to control and reduce trace elements contamination of agricultural soils at both national and regional (departmental) scales.