摘要：In 2001, Maryland’s court of appeals was asked to decide whether researchers at Johns Hopkins University had engaged in unethical research on children. During the 1990s, Johns Hopkins’s Kennedy Krieger Institute had studied 108 African American children, aged 6 months to 6 years, to find an inexpensive and “practical” means to ameliorate lead poisoning. We have outlined the arguments in the case and the conundrum faced by public health researchers as they confront new threats to our health from environmental and industrial insults. We examined the case in light of contemporary public health ideology, which prioritizes harm reduction over the historical goals of prevention. As new synthetic toxins—such as bisphenyl A, polychlorinated biphenyls, other chlorinated hydrocarbons, tobacco, vinyl, and asbestos—are discovered to be biologically disruptive and disease producing at low levels, lead provides a window into the troubling dilemmas public health will have to confront in the future. IN MAY 2012, THE CENTERS for Disease Control and Prevention officially accepted the recommendations of its Advisory Committee on Childhood Lead Poisoning Prevention and adopted a new, lower standard for “acceptable” blood lead levels in American children. The new standard of 5 micrograms per deciliter of blood halved the older definition of 10 micrograms established 20 years ago and nearly doubled the scope of the lead poisoning epidemic in the United States as the estimated number of at-risk children jumped from about a quarter of a million to nearly one half a million victims. 1 This staggering number of children whose neurologic integrity, intelligence, and behavior have been threatened by lead makes this epidemic among the broadest and longest lasting in American public health history. 2 As public health professionals have uncovered the negative effects of ever-lower exposures to lead, their frustration with the lack of political will to eliminate lead from the walls, soil, and air has grown. For the past 30 years—since the confluence of documentation of the widespread damage to children from low levels of lead and the growing strength of conservative, antigovernment ideology in the broader culture and in government—the public health community has been divided on how to proceed in the future: should we demand a massive program to eliminate lead paint on older structures, the major source of lead in the children’s environment, or should we reduce exposures through various abatement procedures, knowing that low-level lead exposures still threaten poor children living in decaying, older homes? These questions about how to address this age-old hazard are not new but have gained increasing urgency as we discover that there very well may not be any threshold below which lead does not negatively affect children’s neurologic development. No case encapsulates the tensions that have arisen over the conflicting approaches to the epidemic better than the Johns Hopkins Bloomberg School of Public Health’s experience with a lead abatement research project it conducted in the 1990s. That study achieved notoriety because in August 2001, just weeks before the attack on the World Trade Center and the Pentagon diverted the nation’s attention, the Court of Appeals of Maryland, that state’s highest court, handed down a strongly worded, even shocking, opinion that goes to the heart of beliefs about what public health should do and what our responsibility to others should be. 3 Open in a separate window The court had been asked to decide whether researchers at Johns Hopkins University, among the nation’s most prestigious academic institutions, had engaged in unethical research on children. The case pitted two African American children and their families against the Kennedy Krieger Institute (KKI), Johns Hopkins’s children’s clinic and research center, which in the 1990s had conducted a multiyear study in which children were exposed to differing amounts of lead in their homes. The KKI project was designed during the presidency of George H. W. Bush to find a relatively inexpensive and effective method for reducing—though not eliminating—the amount of lead in children’s homes and thereby reducing the devastating effect of lead exposure on children’s brains and, ultimately, on their life chances. The Johns Hopkins researchers had recruited 108 families with young children to live in houses with differing levels of lead, ranging from none to levels just below the existing legal limit in Baltimore, Maryland, and then measured the extent of lead in the children’s blood at periodic intervals. (The overwhelming majority of families were composed of single African American mothers and their children.) By matching the expense of varying levels of partial lead paint abatement—a $1650 investment for the first group of homes, $3500 for the second, and $7000 for the third—with changing levels of lead found in the blood, the researchers hoped to find the most cost-effective means of reducing childhood exposure to the toxin. Completely removing lead paint from the homes, the researchers recognized, would be ideal for children’s health, but they believed, with some justification, that to do so would be considered far too costly in such politically conservative times and likely to result in landlord abandonment of housing in the city’s more poverty-stricken districts. The court of appeals found that Johns Hopkins had engaged in highly suspect research that had direct parallels with some of the most infamous incidents of research abuse of vulnerable populations in the 20th century. The KKI Repair and Maintenance Project, the court argued, differed from but presented similar problems as those in the Tuskegee Syphilis Study, … the intentional exposure of soldiers to radiation in the 1940s and 50s, the test involving the exposure of Navajo miners to radiation … and the secret administration of LSD to soldiers by the CIA and the army in the 1950s and 60s. The research defied many aspects of the Nuremberg Code, the court said. 4 For the court it was deeply troubling that a major university would conduct research that might eventuate in permanent damage to children. Many in the public health community later argued that this was just a “rogue court,” an out-of-control panel of judges, but the Maryland Court of Appeals was not known for its liberalism. In fact, the judge who wrote the opinion, Dale R. Cathell, was considered one of the more conservative judges on the bench. 5 The researchers were not uncaring researchers or unfeeling persons either. In fact, one, J. Julian Chisolm, had dedicated his professional life to uncovering the extent and limiting the damage of lead poisoning in Baltimore, and the other, Mark Farfel, was a young committed public health advocate who had formed close alliances with many in the poor community surrounding Johns Hopkins. This was a complex and troubling story, not just about the KKI research but also about the public health profession, the nation’s dedication to the health of its citizens in the new millennium, and the conundrum that we as a society face as we confront revelations about many new environmental threats in the midst of a very conservative political culture and the continuing legacy of poverty and racism. In its ubiquity and harm, lead is an exemplary instance of these threats. Yet there are many others we encounter in everyday life that entail similar issues, from mercury in the fish we eat that comes from power plants to flame retardants used on our children’s clothes and bisphenol A, which is in many plastics, cans, and glues that we commonly use. 6 For much of its history the public health field has provided the vision and the technical expertise for remedying the conditions—both biological and social—that created environments conducive to harm and in which disease could spread. And throughout much of its history, public health leaders have joined with social activists to finds ways in the existing political and economic structures to prevent diseases. Although the medical profession has often been given the credit for the vast improvements in the health and life span of Americans over the past century, it was the crusading spirit of public health reformers in the 19th and early 20th centuries who pushed for housing reforms, mass vaccination campaigns, clean water and sewage systems, and pure food laws that played the major role in improving children’s health, lowering infant mortality, and limiting the impact of viral and bacterial diseases such as cholera, typhoid, diphtheria, smallpox, tuberculosis, measles, and whooping cough that had plagued the nation for decade after decade. These broad public health campaigns to control infectious diseases yielded great victories from the 1890s through the 1930s. With the first decades of the 20th century, however, a different view of the profession slowly began to gain ascendancy, redefining the mission of public health in ways that belied its role as an agent of social reform. In this view, the idea was to put the fast-growing science of biological medicine in the service, not of eradicating the conditions that facilitated disease and its spread but of concentrating on treating the disease itself person by person and reducing risk rather than eliminating it. 7
