News: New reporting rules for endocrine-modulating chemicals considered

Government.     

Towards a dietary-exposome assessment of chemicals in food: An update on the chronic health risks for the European consumer

Abstract

An informed opinion to a hugely important question, whether the food on the Europeans’ plate is safe to eat, is provided. Today, the Europeans face food-borne health risks from non-communicable diseases induced by excess body weight, outbreaks caused by pathogens, antimicrobial resistance and exposures to chemical contaminants. In this review, these risks are first put in an order of importance. Then, not only potentially injurious dietary chemicals are discussed but also beneficial factors of the food. This review can be regarded as an attempt towards a dietary-exposome evaluation of the chemicals, the average European adult consumers could chronically expose to during their life-times. Risk ranking reveals that currently the European adults are chronically exposed to a mixture of potentially genotoxic-carcinogenic contaminants, particularly food process contaminants, at the potential risk levels. Furthermore, several of the contaminants whose dietary exposures pose risks appear to be carcinogens operating with a genotoxic mode of action targeting the liver. This suggests that combined health risks from the exposure to a mixture of the chemical contaminants poses a greater potential risk than the risks assessed for single compounds. Over 100 European-level risk assessments are examined. Finally, the importance of a diversified and balanced diet is emphasized.     

News: EPA again delays mercury risk report release; will seek new reviews, wait for more data

Science.     

Pilot implementation of a newly developed bovine leukemia virus control program on 11 Alberta dairy farms

We developed a custom bovine leukemia virus (BLV) control program for the Alberta dairy industry, consisting of a risk assessment and a comprehensive list of best management practices (BMP) aimed at prevention of BLV transmission between cattle. This control program was implemented on 11 farms for approximately 1 yr. Blood samples were collected from all cattle ≥12 mo old, and serum was tested with a commercial ELISA. Risk assessments were performed on each farm, risk-connected on-farm management was identified, and management changes expected to prevent transmission of BLV between cattle were suggested by the first author and agreed upon with each farmer. Throughout the following year, all participating farmers were visited multiple times to identify and overcome barriers to implementation and to monitor progress. After approximately 1 yr of implementing BLV control, all cattle ≥12 mo old on farm with a negative or no previous test result were sampled, and the within-herd prevalence was determined. The median number of cattle on farm that were ≥12 mo was 195 (range 110–524). The initial prevalence averaged 39% (13–66%). On average, 5 BMP (3–7) were suggested to each farmer. On average, 4 BMP (1–7) were implemented. At the second sampling, the average within-herd prevalence of all animals that tested positive (including the previous sampling) was 36% (12–62%). Eight farms reduced their within-herd BLV prevalence, within-herd prevalence stayed constant on 1 farm, and it increased on 1 farm. The remaining farm terminated their participation before the second sampling. The number of seroconversions per farm ranged from 3 to 109, highlighting the success of some producers to minimize new infections. The risk assessment was proven to be a valuable tool to identify flaws in on-farm management, although risk assessment score was unrelated to the within-herd BLV prevalence. Finally, it appeared that implementation of BMP aimed at prevention of BLV transmission between cattle could reduce within-herd BLV prevalence when farmers committed to their implementation.     

红心火龙果富硒红茶复合饮料加工工艺

为了开发一款功能性的复合富硒植物固体饮料,本研究以药食同源富硒西兰花、葛根、藤茶、黄精、木瓜和西红柿为原料,成功开发出一款复合植物固体饮料。同时,对其抗肿瘤细胞增殖活性、抗氧化活性和镇痛活性进行了评价。利用荧光光度法测定该复合富硒植物固体饮料的总硒含量为540±30.12 μg/kg。功能性评价结果表明该复合固体饮料在100 μg/mL浓度下,能够一定程度的抑制肿瘤细胞（A549、SMMC-7721、MCF-7和SW480）的增殖,抑制率分别为4.09%±1.36%、19.48%±3.18%、30.75%±1.45%和18.20%±1.12%,且对人正常肺上皮细胞BEAS-2B无细胞毒性,具有一定的体外抗肿瘤活性。该复合固体饮料的DPPH自由基清除率呈现浓度依赖性升高,IC₅₀为435.6±27.2 μg/mL。该固体饮料能降低H₂O₂诱导的LO2细胞的氧化损伤和细胞内活性氧水平,且在5~20 μg/mL浓度下呈现剂量和效应相关性,表现出明显的抗氧化活性（P<0.01）。此外,该复合富硒植物固体饮料高剂量组（250 mg/kg）具有显著的镇痛作用（P<0.001）,其镇痛抑制率为92.3%,其镇痛效果与阳性药吗啡（5 mg/kg）的效果相当。本研究结果为复合富硒植物固体饮料进一步开发奠定基础。

     

News: States hope agreement will speed approval of new environmental technologies

Technology.     

News: White House panel creating database of endocrine disrupter-related research

Science.     

Bayesian and time-independent species sensitivity distributions for risk assessment of chemicals

Species sensitivity distributions (SSDs) are increasingly used to analyze toxicity data but have been criticized for a lack of consistency in data inputs, lack of relevance to the real environment, and a lack of transparency in implementation. This paper shows how the Bayesian approach addresses concerns arising from frequentist SSD estimation. Bayesian methodologies are used to estimate SSDs and compare results obtained with time-dependent (LC50) and time-independent (predicted no observed effect concentration) endpoints for the insecticide chlorpyrifos. Uncertainty in the estimation of each SSD is obtained either in the form of a pointwise percentile confidence interval computed by bootstrap regression or an associated credible interval. We demonstrate that uncertainty in SSD estimation can be reduced by applying a Bayesian approach that incorporates expert knowledge and that use of Bayesian methodology permits estimation of an SSD that is more robust to variations in data. The results suggest that even with sparse data sets theoretical criticisms of the SSD approach can be overcome.     

A quantitative risk assessment of the public health impact of the Finnish Salmonella control program for broilers

In order to study the public health effects of the Finnish Salmonella control program (FSCP), a quantitative risk assessment model of Salmonella from slaughtered broiler flocks to consumers was developed. Based on the model, approximately 0.21% of domestically produced broiler meat mass was contaminated with Salmonella (95% probability interval 0.05-0.48%). This model was combined to the model on primary production of broilers. By this way, the effect of eliminating breeder flocks from production which have tested positive for Salmonella and heat-treating the meat of detected positive broiler flocks on public health could be simulated. Based on the whole model, if detected positive breeder flocks were not removed this would result in 1.0-2.5 more reported human cases compared to the expected number of cases under current FSCP (95% predictive interval). Without heat treatment of meat the increase would be 2.9-5.4-fold and without both interventions 3.8-9.0-fold. In scenarios with one grandparent or five parent flocks infected, the combined effect of these two interventions was 9.3-25.8-fold and 4.9-11.7-fold compared to the baseline level under each scenario, respectively. The scenario analyses suggest that with a higher infection level, inclusion of both interventions will be more effective than either of the interventions alone. Replacement of half of the current retail broiler meat by meat with 20-40% contamination could result in 33-93 times more human cases compared to the expected value under current situations. On the basis of the model, the interventions applied in FSCP clearly protect the public health.     

News: New Jersey pilot program eases permit path for companies that cut toxics

Government.     

Chronic dietary risk for pesticide residues in food in Brazil: an update.

The objective was to conduct a dietary risk assessment of pesticides registered in Brazil up to 14 January 2004. The theoretical maximum daily intake (TMDI) was calculated for 275 compounds using the Brazilian maximum residue limits (MRL) and food consumption. The chronic dietary risk assessment was conducted by comparing the TMDI with the Brazilian acceptable daily intake (ADI) or, when not available, with the ADI from other sources. The TMDI was higher than the ADI (%ADI>100) in at least one Brazilian region for eight pesticides, including five organophosphorus insecticides. For these compounds, the higher TMDI (expressed as %ADI) ranged from 140 (metam sodium) to 14,000 (methyl bromide). Rice, beans, citrus and tomato were the commodities that contributed most to ingestion. Change in pesticide use patterns and the establishment of ADIs by the Brazilian government have reduced the number of compounds for which the TMDI exceeded the ADI in the last 4 years. Risk assessment methodology based on TMDI calculation, however, is conservative as it assumes that the food supply is always treated with all the registered pesticides for that crop and that one always consumes food containing residues at the tolerance level. Furthermore, for six compounds with TMDI exceeding the ADI, a more realistic estimation of the pesticide daily intake was conducted using monitoring residue data from the Brazilian National Pesticide Residue Program. For these compounds, the higher refined intakes ranged from 2% (dimethoate) to 180% (fenitrothion) of the ADIs. The implementation of a national pesticide residue monitoring programme by the government was important to allow the refinement of the risk assessment. However, adequate daily food consumption data are still needed to assess better the public health risk to Brazilian consumers from food produced from crops treated with pesticides.