RESUMO
A survey was conducted to determine the distribution and determinants of environmental and blood lead levels near a conventional and several cottage lead smelters and to assess the relationship between environmental and blood lead levels in a tropical, developing-country setting. Fifty-eight households were studied in the Red Pond community, the site of the established smelter and several backyard smelters, and 21 households were studied in the adjacent, upwind Ebony Vale community in Saint Catherine Parish, Jamaica. Households were investigated, using questionnaires, soil and housedust lead measurements, and blood lead (PbB) measurements from 372 residents. Soil lead levels in Red Pond exceeded 500 parts per million (ppm) at 24% of households (maximum--18,600 ppm), compared to 0% in Ebony Vale (maximum 150 ppm). Geometric mean PbB in Red Pond, where 44% of children less than 6 years of age had PbB levels greater than or equal to 25 micrograms per deciliter (micrograms/dL), was more than twice that Ebony Vale in all age groups (p less than 0.0005). Within Red Pond, proximity to backyard smelters and to the conventional smelter were independent predictors of soil lead (p less than 0.05). Soil lead was the strongest predictor of PbB among Red Pond subjects under 12 years of age. The blood lead--soil lead relationship in children differed from that reported in developed countries; blood lead levels were higher than expected for the household-specific soil lead levels that were observed.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Poeira/análise , Chumbo/sangue , Metalurgia , Poluentes do Solo/sangue , Solo/análise , Criança , Pré-Escolar , Países em Desenvolvimento , Humanos , Lactente , Jamaica , Chumbo/análise , Poluentes do Solo/análise , Clima TropicalRESUMO
To investigate the risk of lead poisoning among household members exposed to 'backyard' battery repair shops (BBRS) in Kingston, Jamaica, environmental and blood lead (PbB) were measured at 24 households (112 individuals) with a BBRS worker or located at a BBRS premises and at 18 neighbourhood control households (74 individuals). Elevated PbB (greater than or equal to 25 micrograms per decilitre [micrograms/dl]) was common among subjects of all ages living at BBRS premises, especially among children less than age 12, 43% of whom had PbB greater than 70 micrograms/dl. Potentially hazardous soil and house dust lead levels were also common at BBRS premises, where 84% of yards had soil lead levels above 500 parts per million (geometric mean 3388 parts per million [ppm] at BBRS premises households with a BBRS worker). Geometric mean blood and environmental lead levels were significantly lower at control households, where less than 10% of subjects in all age groups had elevated PbB (maximum 33 micrograms/dl). Sharing a premises with a BBRS was a stronger determinant of household blood lead and environmental contamination than was the presence of a BBRS worker in a household. Blood lead levels were associated with soil and house dust lead levels in all age groups. We conclude that small battery repair shops, which have also been described in other developing countries, create a high lead poisoning risk for nearby residents.
Assuntos
Automóveis , Indústrias , Intoxicação por Chumbo/etiologia , Doenças Profissionais/induzido quimicamente , Características de Residência/estatística & dados numéricos , Adolescente , Adulto , Criança , Poeira/efeitos adversos , Feminino , Humanos , Jamaica , Chumbo/sangue , Intoxicação por Chumbo/sangue , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/sangueRESUMO
To assess lead exposure in the Jamaican lead-acid battery industry, we surveyed three battery manufacturers (including 46 production workers) and 10 battery repair shops (including 23 battery repair workers). Engineering controls and respiratory protection were judged to be inadequate at battery manufacturers and battery repair shops. At manufacturers, 38 of 42 air samples for lead exceeded a work-shift time-weighted average concentration of 0.050 mg/m3 (range 0.030-5.3 mg/m3), and nine samples exceeded 0.50 mg/m3. Only one of seven air samples at repair shops exceeded 0.050 mg/m3 (range 0.003-0.066 mg/m3). Repair shop workers, however, had higher blood lead levels than manufacturing workers (65% vs. 28% with blood lead levels above 60 micrograms/dl, respectively). Manufacturing workers had a higher prevalence of safe hygienic practices and a recent interval of minimal production had occurred at one of the battery manufacturers. Workers with blood lead levels above 60 micrograms/dl tended to have higher prevalences of most symptoms of lead toxicity than did workers with lower blood lead levels, but this finding was not consistent or statistically significant. The relationship between zinc protoporphyrin concentrations and increasing blood lead concentrations was consistent with that described among workers in developed countries. The high risk of lead toxicity among Jamaican battery workers is consistent with studies of battery workers in other developing countries.
Assuntos
Países em Desenvolvimento , Intoxicação por Chumbo/epidemiologia , Chumbo/sangue , Doenças Profissionais/induzido quimicamente , Adulto , Poluentes Ocupacionais do Ar/análise , Fontes de Energia Elétrica , Humanos , Jamaica , Masculino , Doenças Profissionais/epidemiologia , Fatores de RiscoRESUMO
We previously demonstrated a negative correlation between blood lead level and motor nerve conduction velocity in 202 asymptomatic 5 to 9-year-old children living near a lead smelter in Idaho. Blood lead levels ranged from 13 to 97 micrograms/dL. To determine whether a threshold exists between blood lead level and maximal motor nerve conduction velocity, we conducted three regression analyses on these data: a "hockey stick" regression, a logistic regression, and a quadratic regression. We found evidence for a threshold in all three analyses: at a blood level of 30 micrograms/dL in the "hockey stick" regression, at 20 micrograms/dL in the logistic, and at 25 to 30 micrograms/dL in the quadratic. Neither age, sex, socioeconomic status, nor duration of residence near the smelter significantly modified the relationship. These analyses confirm that asymptomatic increased lead absorption causes slowing of nerve conduction, but they also indicate that measurement of maximal motor nerve conduction velocity is an insensitive screen for low-level lead toxicity.
Assuntos
Intoxicação por Chumbo/fisiopatologia , Chumbo/sangue , Condução Nervosa , Doenças do Sistema Nervoso Periférico/fisiopatologia , Criança , Pré-Escolar , Exposição Ambiental , Humanos , Idaho , Intoxicação por Chumbo/sangue , Intoxicação por Chumbo/epidemiologia , Doenças do Sistema Nervoso Periférico/etiologia , Nervo Fibular/fisiopatologiaRESUMO
In a community of potters in Barbados where lead glazes traditionally have been used, a survey of 12 potters, 19 of their family members, and 24 controls revealed elevated blood lead levels in the potters, their family members, and the neighbours who used pottery for culinary purposes. Dust from the potters' homes and work areas contained lead in concentrations up to 320,000 ppm. Pottery was found to have lead release levels up to 3,125 microgram/ml. Six people had upper extremity tremor associated with elevated blood lead levels. This survey demonstrates the risk of using lead glazes in pottery production to family members of potters as well as the potters themselves and emphasizes the need for surveillance of occupational hazards in developing countries.
Assuntos
Arte , Chumbo/sangue , Adolescente , Adulto , Barbados , Criança , Utensílios de Alimentação e Culinária , Poeira , Feminino , Humanos , Intoxicação por Chumbo/epidemiologia , Intoxicação por Chumbo/etiologia , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/induzido quimicamente , Doenças Profissionais/epidemiologia , RiscoRESUMO
Studies to evaluate the prevalence, sources, and health consequences of lead absorption were conducted among children living near a primary lead smelter. Lead levels in air, soil, and dust were highest at the smelter and decreased with distance. Ninety-nine percent of one- to nine-year-old children living within 1.6 kilometers had blood lead levels greater than or equal 40 mug/dl, indicating increased absorption, and 22% had levels greater than or equal 80 mug/dl. The prevalence of lead levels greater than or equal 40 mug/dl decreased with distance; at 72 kilometers from the smelter it was 1%. Erythrocyte protoporphyrin levels increased with blood lead levels: 17% of children with lead levels of greater than or equal 80 mug/dl were anemic. There was no overt neurologic toxicity. Significant negative correlation was found in 202 five- to nine-year-old children between blood lead levels and motor nerve conduction velocity (r = 0.38, p less than 0.02).