Search PubMed⌕ Search

Biomedical subjects

M Gochfeld

Publications and source records attributed to M Gochfeld.

At least 127 records · Page 7Linked to original sources

Lead and behavioral development: effects of varying dosage and schedule on survival and performance of young common terns (Sterna hirundo).

Exposure to lead early in life is known to affect behavioral development. Young common terns (Sterna hirundo) were injected with lead nitrate solution (0.2-1.2 mg/g) or sterile saline to examine the dose-response curve for behavioral effects. Exposed chicks received a dose of lead on d 3 or on d 3 and 7. Behavioral tests 2 d after each injection included visual cliff performance, locomotion, and righting response. Survival depended not only on dose but also on whether chicks received one or two injections. Despite the narrow range of doses, behavioral differences were noted for all measures as a function of dose. The initial lead dose affected behavior more than the second dose, despite the fact that birds receiving a divided dose were more likely to die.

Animals↗

Effects of lead on growth in young herring gulls (Larus argentatus).

One-day-old herring gulls (Larus argentatus) were injected intraperitoneally with lead nitrate solution (0.1 or 0.2 mg Pb/g) or sterile saline to examine differences in growth rates. Despite the low levels of lead exposure, by d 8 there were significant differences in growth rates as a function of treatment. There were also, by d 8, significant differences in bill length, tarsus length, and wing bone length. Except for bill length, these differences persisted for the duration of the study. Developmental curves varied, with lead-treated birds reaching the same asymptote as control birds for bill length, but having a lower asymptote for tarsus length. For curves where asymptotes were reached, lead-treated birds required more days to reach it than control birds. The initial amount of food eaten each day was positively correlated with weight gain for control birds, but negatively correlated for lead-treated birds.

Animals↗

Utility of occupational blood pressure screening for the detection of potential hypertension.

A potential limiting factor in the detection and control of hypertension has been the assumption that a routine periodic sphygmomanometric blood pressure recording is characteristic of usual blood pressure throughout the activities of daily living. The relationship between routine periodic clinic blood pressure and ambulatory blood pressure was investigated in employed workers. Ambulatory readings were obtained at regular intervals using an automatic self-inflating and recording sphygmomanometer at home and at work. Mean ambulatory systolic and diastolic pressures were significantly higher than clinic pressures, both at home and at work, and in every position except reclining. Eleven of the 113 employees considered normotensive from clinic screening had an average of 46% of their diastolic ambulatory readings greater than or equal to 90. These persons may be considered functionally hypertensive. The authors suggest the need to focus attention on those persons with high-normal clinic blood pressures discovered in workplace screening.

Adult↗

Heavy metal concentrations in the liver of three duck species: influence of species and sex.

To investigate interspecific and intersex differences in heavy metal levels, we analysed concentrations of cadmium, cobalt, chromium, copper, lead, mercury, manganese, nickel and zinc in the livers of male and female black duck (Anas rubripes), mallard (A. platyrhynchos) and greater scaup (Aythya marila) collected in Raritan Bay, New Jersey in December 1980 and January 1981. Certain metal levels varied significantly by species and sex. In all species, Zn and Cu had the highest concentrations, and Cd, Co, and Hg were lowest in all three species. Scaup had significantly higher levels of Cu than black ducks and mallards, and mallards had significantly higher levels of Mn and Zn than black duck and scaup. Overall, eight of nine metal levels were higher in male than female black duck. In scaup, females had significantly higher levels of Pb and Mn than males. In black ducks, males had significantly higher levels of Cu, Mn and Zn than females. The sample of mallard was too small to test intersex differences.

Journal Article↗

A hypothesis on the role of pheromones on age of menarche.

Over the last century and a half there has been a secular decline in the age of menarche in Western, industrialized cultures. This trend has been largely ascribed to improved nutrition and health, and we offer an alternative hypothesis that changes in socio-economic conditions have resulted in changes in the pheromonal climate to which prepubertal females are exposed, thereby affecting onset of menarche. Extensive data from non-human mammalian studies indicate that puberty in females is delayed by exposure to adult females, and accelerated by exposure to adult males. The mechanism is pheromonal. The pheromonal climate of the home may have changed since mothers are in the home less (more women now work) and fathers are in the home more (work day of 8 rather than 14 hr). Assuming humans respond similarly to pheromones, this change would contribute to a decline in age of menarche.

Adolescent↗

Comparisons of nine heavy metals in salt gland and liver of greater scaup (Aythya marila), black duck (Anas rubripes) and mallard (A. platyrhynchos).

Levels of nine heavy metals were measured in the livers and salt glands of greater scaup (Aythya marila), black duck (Anas rubripes) and mallard (A. platyrhynchos) from Raritan Bay, New Jersey to determine if the functioning avian salt gland concentrates heavy metals. Heavy metals examined were cadmium, cobalt, chromium, copper, lead, mercury, manganese, nickel and zinc. Heavy metal levels varied significantly by species and tissue for chromium, copper, lead, and manganese, and by tissue for cobalt, mercury, nickel and zinc. In comparing tissues cobalt was higher in the salt glands than in livers of all three species; chromium and nickel were higher in the salt gland than liver for mallard and black duck; and lead, manganese and zinc were higher in the liver than the salt gland in greater scaup. Generally metal levels were higher in the salt gland for mallard and black duck, and in the liver for greater scaup.

Animals↗

Early postnatal lead exposure: behavioral effects in common tern chicks (Sterna hirundo).

Exposure to lead early in life is known to affect behavioral and intellectual development. To develop an animal model we chose the common tern, Sterna hirundo, a species whose early developmental landmarks are well known. One potential for avian models lies in the reliance of birds on visual and acoustic rather than olfactory (and ultrasonic) modes of communication. One randomly chosen member of each of 8 pairs of young common tern chicks was injected with lead nitrate solution at a concentration of 0.2 mg/g. The pairs were not siblings but were matched for age (+/- 1 d) and weight (+/- 3 g). The second member of each pair was injected with an equal volume of sterile saline. Behavioral tests performed examined locomotion, balance and righting response, feeding tasks and begging, depth perception and response on a visual cliff, and behavioral thermoregulation. In each pair the control chick was heavier at 4 wk of age. For most behavioral measures, except begging and movement on a stationary incline, the lead-injected chicks performed less well than the control chicks. When presented with a novel feeding situation (reversal of fish position), the lead-injected chicks required significantly more time to eat the same number of fish. The single injection of lead thus affected a variety of behavioral patterns, with effects apparent within 5 d after injection.

Analysis of Variance↗

Factors influencing tetrachloroethylene concentrations in residences above dry-cleaning establishments.

Indoor air quality has been increasingly recognized as a significant public health problem. Proximity to industrial or commercial sources contributes to contamination in homes. Air sampling was conducted at 12 residences in 8 buildings that housed dry cleaners and 6 residential control sites. The authors found that concentrations of tetrachloroethylene, a dry-cleaning solvent, were elevated significantly in residences located in buildings that also housed dry-cleaning establishments (mean = 2.0 mg/m3) relative to their concentrations in control residences (mean = < 0.07 mg/m3 [p < .001]). Tetrachloroethylene concentrations remained elevated when the cleaners were closed on weekends (p < .01). The authors verified that colorimetric detector tubes were a useful screening tool for residences. Also identified were factors that could affect tetrachloroethylene concentrations. The use of exhaust fans and the implementation of required inspection and maintenance requirements by dry cleaners were associated significantly with reduced tetrachloroethylene concentrations in residences (p < .01). In all cases, tetrachloroethylene concentrations exceeded "minimal risk levels" posited by the Agency for Toxic Substances Disease Registry for chronic exposure to tetrachloroethylene. Residents who live in buildings that house dry cleaners may be exposed at concentrations that are of public health concern. Measures that might reduce this exposure were also identified.

Air Pollution, Indoor↗

Mercury and methylmercury exposure in the New Jersey pregnant population.

Methylmercury is a known fetal developmental neurotoxicant. The only significant source of fetal exposure is maternal fish consumption; however, few recent data on exposure of the pregnant population are available. The authors undertook a study of methylmercury exposure in the New Jersey pregnant population to investigate the distribution of exposure and to identify predictors of elevated exposure. Mainly first-trimester pregnant women were recruited through six New Jersey obstetric practices. Hair and blood samples were analyzed for total mercury, and a subset was analyzed for methylmercury. A questionnaire on demographics, life style, and fish-consumption practices was also administered. Although 85-90% of the pregnant population had hair mercury levels that were less than 1.0 microg/gm, 1-2% had levels in a range of possible concern for adverse developmental effects (> 4.0 microg/gm). Regression analysis suggested that blacks and individuals with some college education experienced lower exposures to methylmercury.

Adult↗

Reduced IL-6 levels among individuals in Hudson County, New Jersey, an area contaminated with chromium.

Hudson County, New Jersey, was a major center for the processing of chromium ore. After processing, some of the ore residue that contained low concentrations of chromium became distributed in population centers throughout the county. There now exists concern in the county about possible health effects from chromium exposure. Our previous research suggested that immune-function assays would make useful biomarkers for chromate exposure in humans. Blood samples were drawn from 46 individuals who lived and/or worked in Hudson County and from 47 controls. Only one of the immune-associated assays performed on these samples showed any statistically significant differences between the Hudson County and control groups. The mean level of IL-6 produced by pokeweed mitogen-stimulated mononuclear cells isolated from the Hudson County group was 64% of the control value--a highly significant decrease (p<.001). There was also a significant correlation between the proliferative responses of the mononuclear cells to pokeweed mitogen and the levels of IL-6 produced by these cells. No differences were detected in the IL-6 responses that resulted from age, gender, or smoking status. The reliability of the IL-6 assay was found to be 90%. To our knowledge, there have been no reports, until now, that describe reduced production of any cytokine in individuals who are exposed to chromate.

Cell Division↗