The cultural parameters of lead poisoning: a medical anthropologist's view of intervention in environmental lead exposure

Declines in adult blood lead levels in New York City compared with the United States, 2004-2014

OBJECTIVES

To assess changes in lead exposure in the New York City (NYC) adult population over a 10-year period and to contrast changes with national estimates, overall, and by socio-demographics and smoking status.

METHODS

We used measurements of blood lead levels (BLLs) from NYC resident adults who participated in the NYC Health and Nutrition Examination Surveys (HANES) in 2004 and 2013-2014. We compared estimates of geometric means (GM), 95th percentiles, and prevalence of BLL ≥ 5 µg/dL overall and by subgroups over time, with adults who participated in the National HANES (NHANES) 2001-2004 and 2011-2014.

RESULTS

The GM BLLs among NYC adults declined from 1.79 µg/dL in 2004 to 1.13 µg/dL in 2013-2014 (P < .0001). The declines over this period ranged from 30.1% to 43.2% across socio-demographic groups and smoking status (P < .0001 for all comparisons), and were slightly greater than declines observed nationally. The drop in prevalence of elevated BLLs (≥ 5 µg/dL) was also greater in NYC (4.8-0.5%), compared with NHANES (3.8-2.0%). By 2013-2014, NYC adults with lower annual family income (< $20,000) no longer had higher GM BLLs relative to those with higher incomes (≥ $75,000), a disparity improvement not observed nationally. Likewise, GM BLLs and 95th percentiles for non-Hispanic black adults in NYC were lower than GM BLLs for non-Hispanic white adults. Non-Hispanic Asian adults had the highest GM BLLs compared with other racial/ethnic groups, both in NYC in 2013-14 and nationally in 2011-2014 (1.37 µg/dL, P = .1048 and 1.22 µg/dL, P = .0004, respectively).

CONCLUSION

The lessening of disparity in lead exposure across income groups and decreasing exposure at the high end of the distribution among non-Hispanic black and Asian adults in NYC suggest that regulatory and outreach efforts have effectively targeted these higher exposure risk groups. However, Asian adults still had the highest average BLL, suggesting a need for enhanced outreach to this group. Local surveillance remains an important tool to monitor BLLs of local populations and to inform initiatives to reduce exposures in those at highest risk.

Use of lead-glazed ceramic ware and lead-based folk remedies in a rural community of Baja California, Mexico

Background:

Lead exposure from lead-glazed ceramics (LGCs) and traditional folk remedies have been identified as significant sources of elevated blood lead levels in Mexico and the United States. This study took place from 2005 to 2012 in a rural community in Baja California, Mexico.

Objectives:

1) Investigate the knowledge, attitudes, and practices related to lead and lead exposures from LGCs and two lead-based folk remedies ( azarcon and greta); and 2) evaluate a pilot intervention to provide alternative lead-safe cookware.

Methods:

A baseline household survey was conducted in 2005, followed by the pilot intervention in 2006, and follow-up surveys in 2007 and 2012. For the pilot intervention, families who reported using LGCs were given lead-safe alternative cookware to try and its acceptance was evaluated in the following year.

Results:

The community was mostly of indigenous background from Oaxaca and a high proportion of households had young children. In 2006, all participants using traditional ceramic ware at the time ( n = 48) accepted lead-safe alternative cookware to try, and 97% reported that they were willing to exchange traditional ceramic ware for lead-safe alternatives. The use of ceramic cookware decreased from over 90% during respondents’ childhood household use in Oaxaca to 47% in 2006 among households in Baja California, and further reduced to 16.8% in 2012. While empacho, a folk illness, was widely recognized as an intestinal disorder, there was almost universal unfamiliarity with the use and knowledge of azarcon and greta for its treatment.

Conclusion:

This pilot evaluation provides evidence 1) for an effective and innovative strategy to reduce lead exposure from LGCs and 2) of the feasibility of substituting lead-free alternative cookware for traditional ceramic ware in a rural indigenous community, when delivered in a culturally appropriate manner with health education. This strategy could complement other approaches to reduce exposure to lead from LGCs.

Bacterial antimicrobial metal ion resistance

Metals such as mercury, arsenic, copper and silver have been used in various forms as antimicrobials for thousands of years with until recently, little understanding of their mode of action. The discovery of antibiotics and new organic antimicrobial compounds during the twentieth century saw a general decline in the clinical use of antimicrobial metal compounds, with the exception of the rediscovery of the use of silver for burns treatments and niche uses for other metal compounds. Antibiotics and new antimicrobials were regarded as being safer for the patient and more effective than the metal-based compounds they supplanted. Bacterial metal ion resistances were first discovered in the second half of the twentieth century. The detailed mechanisms of resistance have now been characterized in a wide range of bacteria. As the use of antimicrobial metals is limited, it is legitimate to ask: are antimicrobial metal resistances in pathogenic and commensal bacteria important now? This review details the new, rediscovered and 'never went away' uses of antimicrobial metals; examines the prevalence and linkage of antimicrobial metal resistance genes to other antimicrobial resistance genes; and examines the evidence for horizontal transfer of these genes between bacteria. Finally, we discuss the possible implications of the widespread dissemination of these resistances on re-emergent uses of antimicrobial metals and how this could impact upon the antibiotic resistance problem.

Community Ecology and Capacity: Keys to Progressing the Environmental Communication of Wicked Problems

Wicked problems are multifactorial in nature and possess no clear resolution due to numerous community stakeholder involvement. We demonstrate childhood lead poisoning as a wicked problem and illustrate how understanding a community's ecology can build community capacity to affect local environmental management by (1) forming an academic-community partnership and (2) developing a place-specific strategy grounded in the cultural-experiential model of risk. We propose that practitioners need to consider a community's ecology and social context of risk as it pertains to wicked problems. These factors will determine how a diverse community interprets and responds to environmental communication and capacity-building efforts.

Lead toxicity as a result of herbal medication

Awareness about the toxic effects of non-essential metals is still lacking in developing countries. Lead is one among them, which ranks second in the Agency for Toxic Substances and Disease Registry' s top 20 lists of toxic metals. Some of the herbal medicines prepared from certain roots and leaves are known to contain this toxic metal at alarming levels. We have a case of a person who suffered from the toxic effects of lead such as vomiting and colicky abdominal pain after consuming a herbal remedy for Jaundice treatment. This went unrecognized initially because of the presence of multiple problems like Malaria and Renal calculi. Lead poisoning as causative factor for anemia, vomiting and colic were confirmed only when blood lead concentration was estimated. A combination of chelation therapy and nutritional supplementation was found to be useful in reducing the body lead burden.

Assessing elemental mercury vapor exposure from cultural and religious practices

Use of elemental mercury in certain cultural and religious practices can cause high exposures to mercury vapor. Uses include sprinkling mercury on the floor of a home or car, burning it in a candle, and mixing it with perfume. Some uses can produce indoor air mercury concentrations one or two orders of magnitude above occupational exposure limits. Exposures resulting from other uses, such as infrequent use of a small bead of mercury, could be well below currently recognized risk levels. Metallic mercury is available at almost all of the 15 botanicas visited in New York, New Jersey, and Pennsylvania, but botanica personnel often deny having mercury for sale when approached by outsiders to these religious and cultural traditions. Actions by public health authorities have driven the mercury trade underground in some locations. Interviews indicate that mercury users are aware that mercury is hazardous, but are not aware of the inhalation exposure risk. We argue against a crackdown by health authorities because it could drive the practices further underground, because high-risk practices may be rare, and because uninformed government intervention could have unfortunate political and civic side effects for some Caribbean and Latin American immigrant groups. We recommend an outreach and education program involving religious and community leaders, botanica personnel, and other mercury users.

The conceptual structure of the integrated exposure uptake biokinetic model for lead in children

The integrated exposure uptake biokinetic model for lead in children was developed to provide plausible blood lead distributions corresponding to particular combinations of multimedia lead exposure. The model is based on a set of equations that convert lead exposure (expressed as micrograms per day) to blood lead concentration (expressed as micrograms per deciliter) by quantitatively mimicking the physiologic processes that determine blood lead concentration. The exposures from air, food, water, soil, and dust are modeled independently by several routes. Amounts of lead absorbed are modeled independently for air, food, water, and soil/dust, then combined as a single input to the blood plasma reservoir of the body. Lead in the blood plasma reservoir, which includes extracellular fluids, is mathematically allocated to all tissues of the body using age-specific biokinetic parameters. The model calculation provides the estimate for blood lead concentration for that age. This value is treated as the geometric mean of possible values for a single child, or the geometric mean of expected values for a population of children exposed to the same lead concentrations. The distribution of blood lead concentrations about this geometric mean is estimated using a geometric standard deviation, typically 1.6, derived from the analysis of well-conducted community blood studies.

Heavy metal toxicity, part II: lead and metal fume fever

This review is the second of a two-part review of heavy metal toxicity. This part will identify the salient features of the toxicopathophysiology, clinical presentation, and emergency department management of lead toxicity and metal fume fever.

Childhood lead poisoning in Africa: a growing public health problem

Gasoline sold in most African countries contain 0.5-0.8 g/l lead. In urban and rural areas and near mining centers, average lead concentrations reach 0.5-3.0 mu g/m3 in the atmosphere and > 1000 mu g/g in dust and soils. In addition to automotive and industrial sources, cottage industries and the burning of paper products, discarded rubber, battery casings and painted woods for cooking and heating represent additional hazards to individual households. Lead paint, lead solder and lead cosmetics are unregulated in some countries. Although African children are particularly predisposed to environmental lead exposure, because of their lifestyle and socioecological factors, a true picture of childhood lead poisoning in the continent remains undefined. Recent prevalence studies show that over 90% of the children in urban and rural communities of the Cape Province, South Africa have blood lead levels > or = 10 mu g/dl. Studies in other countries likewise suggest that childhood lead poisoning is a widespread urban health problem throughout the continent.

Hispanic mothers' beliefs and practices regarding selected children's health problems

The purpose of this study was to identify and describe the Hispanic mothers' initial sources of advice and help with children's illnesses; beliefs about the etiology and seriousness of certain children's illnesses, namely, fever, cough, diarrhea, vomiting, conjunctivitis, skin rash, minor wounds, and burns; practices for the management of these children's health problems, including the use of home remedies, if any. Interviews were conducted with 100 women of Hispanic origin who had at least one child age 5 years or less and who were attending a community clinic in a rural area of central California. Mothers' beliefs about problem etiologies varied widely and revealed several misconceptions, folk beliefs, and lack of knowledge. The findings also revealed that only 32% of the mothers used or would use health professionals as the initial source of advice or help with children's problems. The majority of the subjects (81%) admitted to using home remedies to manage children's problems; 17% sought the help of a folk healer (mainly for the treatment of empacho). The various types of home remedies used by mothers were described and included the ingestion or application of certain foods, fluids, herbal teas, or other materials as well as methods to eliminate the perceived causes of the problems. It is important to note that 11% of the mothers had used azarcon or greta (substances containing lead) for treating empacho and other stomach problems in children. The need for culturally responsive and sensitive health care is discussed.

Lead, cadmium, arsenic and zinc in the ecosystem surrounding a lead smelter

A lead smelter has been operating at Belledune in the province of New Brunswick, in eastern Canada, since 1966. This paper presents data on the concentrations of the four primary metals emitted from the smelter - lead, cadmium, arsenic and zinc - which were measured in the terrestrial environment near the smelter and the concentrate transport route. Deposition of these metals to the snowpack and the uptake by grass forage are discussed in relation to non-regulatory guidelines, toxicity and atmospheric emissions. A 1992 snowpack transect survey extending 0.5-40 km northwest, southeast and south of the smelter revealed lead concentrations of 2-3193 ppb, cadmium <0.10-49.7 ppb, arsenic <3.0-72.0 ppb, and zinc 3-401 ppb. Deposition estimates within this zone for lead were between 0.046 and 20.1 kg/ha/yr, cadmium <0.007 and 313 g/ha/yr, arsenic <0.016 and 453 g/ha/yr and zinc 0.020 and 2.52 kg/ha/yr. Concentrations of these metals in the snowpack were highest within 3 km of the smelter and were detectable at greater distances SE of the smelter. Lead was dispersed greater distances from the smelter than cadmium or arsenic. Snowpack samples collected within 5-20 m of the railway contained 140-7270 ppb of lead, 0.4-36.9 ppb of cadmium, <3.0-72.0 ppb of arsenic and 41-13100 ppb of zinc. Grass forage sampled within 0.6-16 km of the smelter contained lead 5-152 ppm, cadmium 0.10-4.1 ppm, and zinc 22-154 ppm. Highest concentrations of lead, cadmium and zinc in grass forage were found were found within 2.2 km of the smelter. Grass forage collected within 10-70 m of the railway contained lead 13-288 ppm, cadmium 0.4-1.3 ppm and zinc 98-831 ppm.

[Current diagnosis and treatment of lead poisoning]

Lead may be an industrial and an environmental hazard which becomes of greater importance every year. Classical symptoms of plumbism are rare, whenever minor clinical signs increase in frequency. Erythrocyte zinc protoporphyrin and delta-aminolaevulinic acid dehydratase are reliable indicators of the importance of the lead poisoning in individuals. The concentration of lead in blood is also a suitable biological indicator as is EDTA mobilization test. The treatment is based on the use of chelating agents such as calcium EDTA or DMSA, but the only solution is reduction or removal of the sources of lead exposure.