PUBLIC HEALTH BRIEFS
Lead Poisoning among Migrant Children In New York State PETER J. SMITH, PE, DOROTHY M. NELSON, MPH AND RALPH E. STEWART, BS
Introduction Lead Poisoning most frequently strikes urban children between the ages of one and six years exposed to poverty, poor housing, and personal deprivation. However, the problem is not limited to the urban dwellers. Studies conducted in two rural counties, Dutchess County, New York and Litchfield County, Connecticut, showed that 9 per cent of the children tested had blood levels in excess of 40 ,g per 100 ml of whole blood.' Another rural study by Tobin and Osband2 conducted in 1971 on lead paint hazards in migrant camps concluded "of the 117 camps studied, 98.3 per cent were positive for lead based paints." Housing used by the 10-12,000 migrants who work in New York State each year covers a wide range of architectural forms and construction materials, including old two story frame farm houses, modem concrete motel-type buildings, mobile homes and single-family cabins. Although migrant children are born to the rural wanderers, they often live much like their impoverished city counterparts. For this reason, in the summers of 1972 and 1974, the New York State Health Department took an in-depth look at children in migrant camps for the possibility of lead
poisoning. Wayne County was selected for the 1972 study of lead poisoning among migrant children because it contained 23 per cent of all the camps in the state and 90 per cent of the families had children. All migrant camps are regulated by the New York State Sanitary Code.3 Both the lead poisoning and migrant labor sections of the New York State Public Health Law4' 5 provided the legal authority needed.
Sanitarians collected paint samples from every interior and exterior surface where deterioration was observed or where there was evidence of gnawing or chewing of wood by children. Additionally, samples were collected from a limited number of intact surfaces, even when not directly accessible to children, for the purpose of giving information on the general prevalence of the leaded paint as well as to locate potentially hazardous surfaces. The lead content of paint was determined by the collecting of paint chips for laboratory analysis using wet chemistry. The use of the X-ray fluorescent analyzer unit was discarded because it had been found not to be sensitive at low concentrations and yielded results in terms of milligrams/sq. centimeter. The State standard for permissible lead content of paint is expressed in terms of per cent of metallic lead based on the total non-volatile content of the paint. Any painted surface which is deteriorating, accessible to children, and where the lead content of the paint is greater than 1 per cent is considered potentially hazardous. Blood and paint samples were analyzed using atomic absorption spectrophotometry. In order to determine the validity of the data obtained in the 1972 survey, and also to expand the program to reach as many migrant children as possible, a screening program was initiated in cooperation with the New York State Department of Agriculture and Markets during the summer of 1974. The micro-method was used in the initial screening of children from selected camps. The macro-technique was used to verify any blood lead levels of 40 micrograms or above per 100 ml of whole blood.
Results
Methods The study was conducted by the Health Department staff assigned to the Migrant Labor Camp Program using policies and procedures which already had been developed. The existing methods and procedures of the State Health Department for collecting blood and paint samples were applied. The macro-method for blood lead determination which requires 5 ml of venous blood was used by the public health nurses or local physicians. The authors are with the New York State Health Department, Albany, NY. Address reprint requests to Ms. Nelson, Lead Poisoning Control Program, New York Department of Health, Tower Building, Empire State Plaza, Albany, NY 12237. This paper, presented at the American Public Health Association's Annual Meeting in New Orleans, LA, was revised and accepted for publication December 1, 1975.
AJPH, April, 1976, Vol. 66, No. 4
In the 1972 survey, 166 paint samples were collected at 97 migrant camps; 92 of the samples were from deteriorating and accessible surfaces and 74 were from intact surfaces. Lead levels of 1 per cent or greater were found in 123 (74 percent) of the samples, with little variation in lead levels being noted between intact and deteriorating surfaces. The percentage of samples with lead levels of 1 per cent or greater was higher than was found in 1972 in high risk areas throughout upstate New York, when 49 per cent of 3,310 samples showed lead levels of I per cent or more. However, the number of deteriorating and accessible surfaces per dwelling unit inspected varied greatly between the two studies. In the 1972 migrant camp survey, 40 per cent of 166 dwelling units inspected had one or more surfaces considered to be potentially hazardous; in upstate New York as a whole, 77 per cent of 331 dwelling units inspected in 1972 in the statewide general lead poisoning control pro383
PUBLIC HEALTH BRIEFS
gram were found to have one or more potentially hazardous surfaces. In 1972, 79 migrant children were screened by nurses in the Day Care Centers. Only one child was found to have an elevated blood lead level and was rescreened within a few weeks and tested below 40 ,ug per 100 ml. During 1972 in upstate New York, 5,733 children from high risk areas were screened; 1,237 children (21.6 per cent) had elevated blood levels.6 An effort was made during the summer of 1974 to determine if the wide discrepancies between the Wayne County migrant survey results of 1972 and the upstate results could be duplicated in other migrant children. A total of 190 children from 5 geographical areas were screened by the micro method at 9 clinics. Nineteen (10 per cent) of these children were found to have elevated blood lead levels by this method (which is less specific than the macro method). Of the 12 children that could be located for rescreening, 9 were found to have levels below 40 ,ug per 100 ml on the second test using the macro method. Even if it is assumed that all seven of the children lost to follow-up had elevated blood lead levels (a highly unlikely assumption given the poorer specificity of micro techniques) only 10 (5 per cent) of the 190 children would have had verified levels about 40 ,ug. During 1974,12 per cent of the children screened in upstate New York as a whole had levels above 40 ,ug.
Discussion In attempting to account for the difference between migrant children and children in the one to six year old age group living in poorer urban areas, the dissimilarities between the two groups of children should be considered. Most migrant children do not become very well acquainted with their dwellings. A family rarely spends more than three months in any one migrant labor camp. Chisolm reports that clinical symptoms and eventually the absorption of potentially lethal body burdens of lead occur after a child repeatedly ingests lead for 3 months or longer.7 Migrant children are not exposed to the many environmental sources of lead to which a city dweller would be. Therefore, pollutants such as automobile exhausts and industrial sources of lead would be remote from migrant children.
384
Most migrant housing in New York State was built after 1950 or so completely renovated that at least the interior surfaces are of recent vintage. There was no requirement that the interior or exterior of migrant labor camps be painted until 1968 when a requirement was introduced which provided that all interior surfaces must be easy to keep clean.3 Unlike much of the older, lower income urban housing, migrant housing for the most part did not deteriorate from higher income housing. Construction was limited to the essentials. Finally, our data comparing migrant children with other children in New York State have not been standardized for age and race, both of which are known to correlate with screening results.
Summary Potentially hazardous painted surfaces were found in 40 per cent of 166 dwelling units surveyed in 97 upstate New York migrant labor camps, a figure substantially lower than comparable surveys in upstate New York high risk urban areas. Blood samples obtained from 79 migrant children in 1972 revealed only one child with blood lead level above 40 ,tg per 100 ml as compared to a 21.6 per cent yield from 5,733 high risk urban area children. A second screening program in 1974 yielded only three children of 190 tested with proven blood lead levels above 40 ,ug per 100 ml, although seven additional children with possible elevations were lost to follow-up.
REFERENCES 1. Cohen, C. J., N. Bowers and M. L. Lepow. Epidemiology of lead poisoning urban and rural children, JAMA, 226:12, pp. 14301433, Dec. 17, 1973. 2. Osband, M. E. and J. R. Tobin. Lead paint exposure in migrant camps, Pediatrics, 49:4, April 1972. 3. New York Codes, Rules and Regulation of the State of New York, Chapter I, Part 15. 4. New York State Public Health Law, Chapter 338, Title X. 5. New York Codes, Rules and Regulations of the State of New York, Chapter II, Part 67. 6. New York State Health Department Records (unpublished). 7. Chisolm, J. J., Jr. Lead poisoning, Scientific American, 224:21 pp. 15-23, Feb. 1971.
AJPH, April, 1976, Vol. 66, No. 4
Lead Poisoning among Migrant Children In New York State PETER J. SMITH, PE, DOROTHY M. NELSON, MPH AND RALPH E. STEWART, BS
Introduction Lead Poisoning most frequently strikes urban children between the ages of one and six years exposed to poverty, poor housing, and personal deprivation. However, the problem is not limited to the urban dwellers. Studies conducted in two rural counties, Dutchess County, New York and Litchfield County, Connecticut, showed that 9 per cent of the children tested had blood levels in excess of 40 ,g per 100 ml of whole blood.' Another rural study by Tobin and Osband2 conducted in 1971 on lead paint hazards in migrant camps concluded "of the 117 camps studied, 98.3 per cent were positive for lead based paints." Housing used by the 10-12,000 migrants who work in New York State each year covers a wide range of architectural forms and construction materials, including old two story frame farm houses, modem concrete motel-type buildings, mobile homes and single-family cabins. Although migrant children are born to the rural wanderers, they often live much like their impoverished city counterparts. For this reason, in the summers of 1972 and 1974, the New York State Health Department took an in-depth look at children in migrant camps for the possibility of lead
poisoning. Wayne County was selected for the 1972 study of lead poisoning among migrant children because it contained 23 per cent of all the camps in the state and 90 per cent of the families had children. All migrant camps are regulated by the New York State Sanitary Code.3 Both the lead poisoning and migrant labor sections of the New York State Public Health Law4' 5 provided the legal authority needed.
Sanitarians collected paint samples from every interior and exterior surface where deterioration was observed or where there was evidence of gnawing or chewing of wood by children. Additionally, samples were collected from a limited number of intact surfaces, even when not directly accessible to children, for the purpose of giving information on the general prevalence of the leaded paint as well as to locate potentially hazardous surfaces. The lead content of paint was determined by the collecting of paint chips for laboratory analysis using wet chemistry. The use of the X-ray fluorescent analyzer unit was discarded because it had been found not to be sensitive at low concentrations and yielded results in terms of milligrams/sq. centimeter. The State standard for permissible lead content of paint is expressed in terms of per cent of metallic lead based on the total non-volatile content of the paint. Any painted surface which is deteriorating, accessible to children, and where the lead content of the paint is greater than 1 per cent is considered potentially hazardous. Blood and paint samples were analyzed using atomic absorption spectrophotometry. In order to determine the validity of the data obtained in the 1972 survey, and also to expand the program to reach as many migrant children as possible, a screening program was initiated in cooperation with the New York State Department of Agriculture and Markets during the summer of 1974. The micro-method was used in the initial screening of children from selected camps. The macro-technique was used to verify any blood lead levels of 40 micrograms or above per 100 ml of whole blood.
Results
Methods The study was conducted by the Health Department staff assigned to the Migrant Labor Camp Program using policies and procedures which already had been developed. The existing methods and procedures of the State Health Department for collecting blood and paint samples were applied. The macro-method for blood lead determination which requires 5 ml of venous blood was used by the public health nurses or local physicians. The authors are with the New York State Health Department, Albany, NY. Address reprint requests to Ms. Nelson, Lead Poisoning Control Program, New York Department of Health, Tower Building, Empire State Plaza, Albany, NY 12237. This paper, presented at the American Public Health Association's Annual Meeting in New Orleans, LA, was revised and accepted for publication December 1, 1975.
AJPH, April, 1976, Vol. 66, No. 4
In the 1972 survey, 166 paint samples were collected at 97 migrant camps; 92 of the samples were from deteriorating and accessible surfaces and 74 were from intact surfaces. Lead levels of 1 per cent or greater were found in 123 (74 percent) of the samples, with little variation in lead levels being noted between intact and deteriorating surfaces. The percentage of samples with lead levels of 1 per cent or greater was higher than was found in 1972 in high risk areas throughout upstate New York, when 49 per cent of 3,310 samples showed lead levels of I per cent or more. However, the number of deteriorating and accessible surfaces per dwelling unit inspected varied greatly between the two studies. In the 1972 migrant camp survey, 40 per cent of 166 dwelling units inspected had one or more surfaces considered to be potentially hazardous; in upstate New York as a whole, 77 per cent of 331 dwelling units inspected in 1972 in the statewide general lead poisoning control pro383
PUBLIC HEALTH BRIEFS
gram were found to have one or more potentially hazardous surfaces. In 1972, 79 migrant children were screened by nurses in the Day Care Centers. Only one child was found to have an elevated blood lead level and was rescreened within a few weeks and tested below 40 ,ug per 100 ml. During 1972 in upstate New York, 5,733 children from high risk areas were screened; 1,237 children (21.6 per cent) had elevated blood levels.6 An effort was made during the summer of 1974 to determine if the wide discrepancies between the Wayne County migrant survey results of 1972 and the upstate results could be duplicated in other migrant children. A total of 190 children from 5 geographical areas were screened by the micro method at 9 clinics. Nineteen (10 per cent) of these children were found to have elevated blood lead levels by this method (which is less specific than the macro method). Of the 12 children that could be located for rescreening, 9 were found to have levels below 40 ,ug per 100 ml on the second test using the macro method. Even if it is assumed that all seven of the children lost to follow-up had elevated blood lead levels (a highly unlikely assumption given the poorer specificity of micro techniques) only 10 (5 per cent) of the 190 children would have had verified levels about 40 ,ug. During 1974,12 per cent of the children screened in upstate New York as a whole had levels above 40 ,ug.
Discussion In attempting to account for the difference between migrant children and children in the one to six year old age group living in poorer urban areas, the dissimilarities between the two groups of children should be considered. Most migrant children do not become very well acquainted with their dwellings. A family rarely spends more than three months in any one migrant labor camp. Chisolm reports that clinical symptoms and eventually the absorption of potentially lethal body burdens of lead occur after a child repeatedly ingests lead for 3 months or longer.7 Migrant children are not exposed to the many environmental sources of lead to which a city dweller would be. Therefore, pollutants such as automobile exhausts and industrial sources of lead would be remote from migrant children.
384
Most migrant housing in New York State was built after 1950 or so completely renovated that at least the interior surfaces are of recent vintage. There was no requirement that the interior or exterior of migrant labor camps be painted until 1968 when a requirement was introduced which provided that all interior surfaces must be easy to keep clean.3 Unlike much of the older, lower income urban housing, migrant housing for the most part did not deteriorate from higher income housing. Construction was limited to the essentials. Finally, our data comparing migrant children with other children in New York State have not been standardized for age and race, both of which are known to correlate with screening results.
Summary Potentially hazardous painted surfaces were found in 40 per cent of 166 dwelling units surveyed in 97 upstate New York migrant labor camps, a figure substantially lower than comparable surveys in upstate New York high risk urban areas. Blood samples obtained from 79 migrant children in 1972 revealed only one child with blood lead level above 40 ,tg per 100 ml as compared to a 21.6 per cent yield from 5,733 high risk urban area children. A second screening program in 1974 yielded only three children of 190 tested with proven blood lead levels above 40 ,ug per 100 ml, although seven additional children with possible elevations were lost to follow-up.
REFERENCES 1. Cohen, C. J., N. Bowers and M. L. Lepow. Epidemiology of lead poisoning urban and rural children, JAMA, 226:12, pp. 14301433, Dec. 17, 1973. 2. Osband, M. E. and J. R. Tobin. Lead paint exposure in migrant camps, Pediatrics, 49:4, April 1972. 3. New York Codes, Rules and Regulation of the State of New York, Chapter I, Part 15. 4. New York State Public Health Law, Chapter 338, Title X. 5. New York Codes, Rules and Regulations of the State of New York, Chapter II, Part 67. 6. New York State Health Department Records (unpublished). 7. Chisolm, J. J., Jr. Lead poisoning, Scientific American, 224:21 pp. 15-23, Feb. 1971.
AJPH, April, 1976, Vol. 66, No. 4
