Health risk assessment conventional

We are working with the Food Quality Control Department of the Ministry of Health to study the contamination of OCPs and PCBs in local fish and chickens. This project is in line with our current effort to assess the health risk arising from consumption of food contaminated with POP chemicals. The health risk assessment of POPs through dietary intakes project involved analyses of OCPs and PCBs in various foodstuff, initially raw materials which will be extended to cooked food. Unfortunately, we do not currently have the capability to analyze PCDD/PCDF in our laboratory but there are two high resolution mass spectrometers in the country that are capable of analyzing PCDD/PCDF. National and international collaborations will definitely improve the country capacity to monitor POPs not only those listed in the Stockholm Convention but other toxic chemicals found in the environment. 

This chapter and the four that follow confine themselves to conventional human health risk assessment, insofar as environmental Pb has been released or continues to be released into the environment in enormous quantities, and conventional risk assessment is the post hoc tool for dealing with these past or ongoing releases. To help link this part with the preceding material. Table 20.1 sets forth the connections. 

THE COMPONENTS OF CONVENTIONAL HUMAN HEALTH RISK ASSESSMENT... 

In considering pesticide residues, it was clearly shown that crops from organic production systems contain no or significantly lower levels of pesticide residues than crops from conventional systems (Baker et al., 2002). However, while some scientists are concerned about the potential health impacts from such residues (Porter et al., 1999 Benbrook, 2002), pesticide legislators maintain that current pesticide risk assessments and pesticide registration procedures are adequate and that residues below the current legal limits can not have a negative health impact in humans (e.g. PSD, 2006). 

EPA research investments since 1995 in pesticide exposure and risk assessment methods have helped pioneer novel approaches to quantify risk levels. A team at the University of Washington s School of Public Health and Community Medicine found that 2-5 year olds consuming predominantly organic foods over a 3-day period had 8.5-fold lower mean levels of OP insecticide metabolites in their urine than children eating mosdy conventional (unlabeled) foods (Curl et al., 2003). The study was carefully designed to minimize potentially... 

Precaution and Environmental Science. When the precautionary principle is discussed in its relationship to science, it is often portrayed as an antiscience or a risk-management principle that is only used after undergoing conventional scientific processes. As discussed earlier, in practice the limitations of science to characterize complex risks show that precaution is not at odds (Kriebel et al., 2001). Further, precaution is not just about additional safety factors or changing risk assessment default assumptions. Research by U.S. EPA scientists has demonstrated that many of the EPA s Reference Doses - or conservative safe exposures - may correspond to risks of greater than 1 in 1000, meaning that safety factors alone may not protect health (Castorina and Woodruff, 2003). 

These two modalities also interact differently with public health policy. Conventional risk assessment helps inform efforts at secondary disease prevention or disease risk prevention by first quantifying the extent of contact with existing toxic substances and then the extent of harm to human and other populations from such toxic substances. The Precautionary Principle... 

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