Double Protection: Reaching Accord on the Ethical Conduct of Child Observational Research
Barrett, Julia R., Environmental Health Perspectives
From Bernardino Ramazzini's visits to seventeenth-century craftsmen's worksites--where he made observations that earned him the title of "father of occupational medicine"--to modern-day research leading to bans on public smoking, observational studies have improved and enhanced environmental health. Such studies involve observing people's everyday lives, defining the characteristics of their environments, and determining whether any risks arise from activities within the context of those environments. Modern environmental observational studies, including the recently launched National Children's Study, also measure environmental compounds and their metabolites in people's bodies while assessing sources and routes of exposure so that the appropriate agencies can initiate reduction strategies if high exposures are seen.
Generally, an observational study is conducted without the observer intervening with research subjects to avoid undermining research goals. However, strict adherence to this practice could create significant ethical concerns, particularly when a vulnerable subject such as a child is at risk for harm. Misunderstandings and disagreements about how those concerns should be addressed in children's observational exposure studies have forced researchers and policy makers to more precisely--and now possibly successfully--define what constitutes a scientifically rigorous and ethical study.
Watch and Learn
Because of their behaviors, stages of development, and smaller size, children often experience a higher level of risk from environmental contaminants than adults. This was recognized in legislation such as the Food Quality Protection Act of 1996, which defined new limits for pesticide exposures and added a tenfold safety margin to previously established limits to provide better protection for children. However, such added protection may be inadequate. "Studies that have been conducted on pesticide exposure in children indicate that assuming kids are affected at tenfold-lower levels than adults is probably an underestimate and not protective enough," says Michael Lebowitz, a retired professor of medicine and epidemiology at The University of Arizona. "We need to understand how to protect the kids, not just what to regulate."
Additionally, pesticides are not the only contaminants to which children are exposed. Data are lacking on a large number of chemicals, including plasticizers and components of personal care products, with regard to exposure levels and the impacts they may have on children. "We don't have the information now to be able to fully regulate," says Lebowitz. "Sometimes we regulate on incomplete information, and sometimes we don't regulate the right way or enough. There are so many toxic compounds that haven't been examined sufficiently for us to know whether to ban them or regulate them."
Furthermore, even well-regulated contaminants such as lead remain a public health concern. Decades of lead regulations have resulted in a significant decrease in the amounts found in children's bodies, but children nevertheless remain at risk. No safe blood lead level has been established, and exposure is a continuing problem--for example, through lead paint being used on imported toys and in the manufacture of artificial turf playing fields. "There are situations where there have been exposures, and there still are exposures. The reason why is that we have an inadequacy in understanding how children come in contact with things and are actually exposed," says Paul Lioy, a professor of environmental and occupational medicine at the University of Medicine and Dentistry, New Jersey-Robert Wood Johnson Medical School.
Groups that have opposed certain observational exposure studies, such as the Washington, DC-based nonprofit Environmental Working Group (EWG), agree that studies are needed, but their design, intended end points, and potential conflicts of interest have been stumbling blocks. …