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Biomedical subjects

M Gochfeld

Publications and source records attributed to M Gochfeld.

At least 73 records · Page 4Linked to original sources
PubMed1997

Lead and neurobehavioral development in gulls: a model for understanding effects in the laboratory and the field.

Animals, including humans, are increasingly exposed to a variety of environmental chemicals that can cause adverse developmental neurobehavioral effects. Most studies either examine effects in the laboratory, or report levels in wild animals, but the relationship between dose, tissue levels and effects are seldom examined in one system. Establishing this relationship is particularly important for endocrine disruptors because of the current controversies regarding impacts on both humans and wildlife. In this paper we synthesize results from a 10-year research program that uses the herring gull chick as a model to examine the relationship between dose, tissue levels, and response to lead in both the laboratory and the wild; and compare levels that cause deficits to those that occur in wild populations of a number of birds. The laboratory studies show that lead affects several aspects of neurobehavioral development in herring gull chicks. There are critical periods for the effects of lead on neurobehavioral development; and there are dissociations: different behaviors have different critical periods. Response latency may be affected most when exposure occurs at one age, while accuracy of response may be affected more at a different age of exposure. Further, there is not necessarily a correlation between impairment and the recovery trajectory. The field experiments show that there are similar lead-induced neurobehavioral deficits in the wild as occur in the laboratory. However, there were important differences: recovery occurred sooner in the field compared to the laboratory; parents partially compensated for the behavioral deficits and succeeded in getting surviving chicks to a similar fledging weight as control chicks, and although survival was decreased in lead-injected chicks in the wild, it was not as low as predicted because of the protective behavior of their parents. These impairments resulted in decreases in survival, which reduced overall fledging rates for a population with lead exposure. Data on exposure levels, as indicated by lead levels in feathers of birds worldwide, suggest that some birds are at risk of neurobehavioral impairment from exposure to lead. Although the neurobehavioral deficits are subtle, and difficult to prove using only wild populations, the data from the field experiments with herring gulls clearly indicate that the deficits occur. This providers a model for studying the neurobehavioral effects of any chemicals on wild populations.

Animals↗
PubMed1996

Heavy metal and selenium levels in Franklin's Gull (Larus pipixcan) parents and their eggs.

Lead, cadmium, mercury, chromium, selenium, and manganese concentrations were measured in the breast feathers of 25 pairs of Franklin's Gull (Larus Pipixcan) and in their eggs from a breeding colony at Agassiz National Wildlife Refuge in Northwestern Minnesota. Metal concentrations in eggs represent metals sequestered in the egg by females at the time of egg formation; while metal concentrations in parents represent concentrations of metals in blood supply at the time of feather formation. There were no significant sexual differences in metal concentrations in feathers, assuming the male to be larger of each pair, but there were significant differences between the concentrations of metals in parents and their eggs. Eggs had significantly higher concentrations of selenium and chromium, but significantly lower concentrations of all other metals than the feathers of their parents. There were few significant correlations among metal concentrations within the egg or within the feather of females, but there were correlations for the feathers of males. Lead and cadmium in feathers were positively correlated for both males and females. Chromium concentrations in eggs were generally higher than reported in the literature. The concentrations in eggs and the feathers of females were positively correlated for mercury, and negatively correlated for chromium and manganese.

Animals↗
PubMed1996

Lead and behavioral development: parental compensation for behaviorally impaired chicks.

Lead is ubiquitous in nature, and can affect behavioral, physiological, and intellectual development in humans and other animals. We used lead-induced behavioral deficits to examine the behavior of parents and young herring gulls in the Captree, NY, gull colony. Our objectives were to determine: a) If there were differences in the behavior, weight, and survival of chicks as a function of treatment; b) if parental behavior varied as a function of treatment; and 3) if there were differences in sibling competition and parent-young conflict between experimental nests (with lead-impaired chicks and control chicks) and control nests. We injected one chick in each of 22 nests (1-2 days of age) with lead acetate (100 mg/kg in sterile water) and injected its sibling with sterile saline, and compared behavior of parents and young (from 1-21 days postinjection). We also observed behavior of parents and chicks in 12 control nests in which chicks were handled similarly but were not injected. There were significant lead-induced differences in righting response, locomotion, thermoregulation, begging, and feeding behavior in the chicks; corroborating observations from the laboratory. Lead-injected chicks were less able to compete for food with their siblings, with a resultant significant difference by weight at 16 days of age. For experimental nests in which the weight difference was great, parents engaged in divided feeding of the brood. After one parent initiated feeding, the other parent walked a short distance away and began to call to and then feed the second, smaller chick. The extra parental care resulted in increased survival for the lead-injected chicks, and in their catching up to their siblings in weight by fledging. The results of this experiment indicate that lead induces behavioral deficits and growth retardation in gulls in nature, decreases survival at young ages, and that parents compensate for these behavioral and growth deficits by brood division for feeding chicks such that by fledging the chicks are no longer at a weight and size disadvantage. Parents are, thus, able to perceive a difference in body size and/or vigor of their offspring, and to behaviorally compensate partially for the lead-induced deficits.

Animals↗
PubMed1995

A pilot study of take-home lead exposure in New Jersey.

Studies in various industries have found an association between worker exposure to lead and elevated blood lead levels in workers' children, but the magnitude of this problem is unknown. In an effort to characterize this problem further, a pilot study was undertaken to obtain blood lead levels of children of lead-exposed workers with elevated blood lead levels who had been reported by laboratories to the New Jersey Department of Health. Fifteen workers' families participated in this study, including 28 children. Thirty-two percent of the children were found to have blood lead levels > or = 10 micrograms/dl, the level of concern set by the Centers for Disease Control and Prevention for medical monitoring. This finding is in contrast to population-based data collected from the Third National Health and Nutrition Survey, where the overall prevalence of blood lead levels > or = 10 micrograms/dl was only 4.5%.

Adolescent↗
PubMed1995

Eggshell thickness in marine birds in the New York Bight--1970s to 1990s.

Maintaining eggshell thickness is critical for birds, as thin eggshells result in breakage during incubation, with subsequent hatching failure. Beginning in the 1960s, eggshell thickness has been used as a biomarker of exposure to chlorinated hydrocarbon pesticides, as a measure of avian population health, and as a predictor of potential reproductive failures. In this study, eggs were collected from four coastal bird species nesting in the New York Bight (Cedar Beach, NY to Barnegat Bay, NJ) in the early 1970s, early 1980s, and early 1990s, and eggshell thickness was measured. We tested the hypothesis that decreasing use of chlorinated hydrocarbons, and subsequent decreased levels of these pollutants in the New York Bight estuarine food web, should have resulted in increased eggshell thickness from the 1970s to the 1990s. Most of the variation in eggshell thickness was explained by decade and species. Eggshell thickness increased from the early 1970s (or the 1980s for some species) to the early 1990s for all four species examined: common tern (Sterna hirundo), Roseate tern (S. dougallii), least tern (S. antillarum), and black skimmer (Rynchops niger). For common terns and black skimmers, eggshell thickness increased by nearly 50% from the 1970s to the 1990s, whereas in the smallest species, the least tern, eggshell thickness increased only by 12%. In the 1990s, least terns with the smallest eggs had the thinnest eggshells, and black skimmers with larger eggs had the thickest eggshells.

Animals↗
PubMed1995

Heavy metal and selenium concentrations in eggs of herring gulls (Larus argentatus): temporal differences from 1989 to 1994.

Concentrations of five metals and selenium in the eggs of herring gulls (Larus argentatus) were examined at a breeding colony on western Long Island, New York from 1989 to 1994. There were significant yearly differences in lead, cadmium, mercury, selenium, chromium, and manganese. Chromium and cadmium were significantly higher in 1993 compared to the other years. Lead levels were highest in 1989, and were uniformly lower in the succeeding four years. Manganese showed no clear pattern. Selenium concentrations decreased from 1991 through 1994, whereas mercury increased from 1992 through 1994. Generally, concentrations of cadmium were similar to those reported for avian eggs from elsewhere; mercury and lead were within the range, but were at the high end; and chromium concentrations were higher than elsewhere. For all years combined, there was a positive correlation between lead and cadmium concentrations and between chromium and manganese, and a negative correlation between lead and mercury concentrations. In conclusion, egg contents can be used to monitor heavy metal concentrations, but consecutive years must be examined because concentrations can vary significantly among years. Ideally, data are needed for more than three years before trends, or lack thereof, can be determined.

Animals↗
PubMed1995

Behavior effects of lead exposure on different days for gull (Larus argentatus) chicks.

Lead exposure early in life affects behavioral, physiologic, and intellectual development in humans and other animals. In this article, we examine the effects of temporal differences in lead exposure on early development in herring gulls (Larus argentatus). Each of 72 1-day-old herring gull chicks was randomly assigned to one of six treatment groups to receive a lead nitrate concentration of 100 micrograms/g at age 2 or at age 6, a similar cumulative dose evenly divided on days 2, 4, and 6, or matched-volume saline injections on the same days. Behavioral tests were performed (some at 2- and others at 5-day intervals) to examine locomotion, balance, righting response, thermoregulation, and visual cliff. Most variation in weight was explained by testing age, although treatment affected weight gain for the lead-6 gulls, particularly after 20 days. Although treatment influenced balance and locomotion, the effect was small. The lead-6 birds were unable to remain on an incline as long as the lead-2, lead-246, and control birds. The overall score for balance improved with age for controls, showed little change for the lead-2 and lead-2-4-6 gulls, but showed a decrease in performance for the lead-6 birds. On the thermoregulation test, the lead-6 birds performed less well under both low- and high-temperature test conditions. Although the lead-2-4-6 birds had a lower score on the visual cliff tests than the other groups, the lead-6 gulls showed a significant delay in response and gave significantly fewer calls then the other groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Growth and behavioral effects of early postnatal chromium and manganese exposure in herring gull (Larus argentatus) chicks.

Organisms in marine environments are exposed to chromium and manganese, yet little is known of the effects of these metals on physiology and behavior. In this article we examine the effects of chromium and manganese on early neurobehavioral development in herring gulls, Larus argentatus. Each of 36 2-day-old herring gull chicks was randomly assigned to one of three treatment groups to receive either chromium nitrate (25 mg/kg), manganese acetate (50 mg/kg), or a control dose of sterile saline solution. The trios were not siblings, but were matched by age and weight. Behavioral tests examined food-begging, balance, locomotion, righting response, recognition, thermoregulation, and perception. There were significant differences in begging behavior by 5 days postinjection, and there were significant differences in weight gain throughout development until 50 days of age, when the experiment was terminated. Behavioral tests, administered from 18-48 days postinjection, indicated significant differences between control and the exposed groups for time to right themselves; thermoregulation behavior; and performance on a balance beam, inclined plane, actual cliff, and visual cliff (although not all components varied significantly). Of the 14 behavioral measures with significant differences, control birds performed best on 12.

Analysis of Variance↗
PubMed1995

Effects of varying temporal exposure to lead on behavioral development in herring gull (Larus argentatus) chicks.

In humans and other animals, lead exposure in infants and young animals affects anatomic, physiologic, behavioral, and intellectual development. Yet it is largely unknown whether the effects occur gradually or are more pronounced if exposure occurs at particular stages. In this article we examine the effects of temporal differences in lead exposure on early behavioral development in herring gulls (Larus argentatus). We randomly assigned 64 1-2-day-old gull chicks to one of four treatment groups to receive a lead acetate dose at age 6 days (100 micrograms/g) or 12 days (50 or 100 micrograms/g), or to receive matched volume saline injections on the same days. Behavioral tests were performed at 2-5-day intervals to examine locomotion, balance, righting response, thermoregulation, and visual cliff. Flight behavior was examined at fledging. Results were compared with previously studied exposures at 2, 4, and 6 days of age. Righting response and balance were disrupted immediately after exposure, regardless of the timing of exposure. Thermoregulatory, visual cliff, and individual recognition behavior were more affected by exposure at 2-6 days, and there was little effect with exposure at 12 days. These results confirm the existence of critical periods for certain behaviors to lead exposure in developing herring gulls.

Aging↗
PubMed1995

Incineration: health and environmental consequences.

Incineration is considered one of the four primary ways to manage solid wastes, in conjunction with source reduction and reuse, recycling-composting, and landfilling. Incineration is currently used to destroy household and institutional solid waste, hazardous chemical waste, and medical and biological waste by reducing volume and destroying some harmful constituents. The process of incineration induces chemical changes that may produce harmful products that can escape through the stack, causing air pollution, or that can remain in the bottom ash, eventually finding a way into landfills. Although sound engineering design and operation can theoretically eliminate most harmful pollutants, strong institutional controls are required to assure that incinerators are maintained and operated according to specifications. Incineration is often viewed as a "cop-out," avoiding the socioeconomically complex changes required to reduce the generation of solid waste. Incineration should be incorporated on a limited basis into a context of comprehensive approaches to source reduction, recycling, and reuse.

Environmental Pollution↗
PubMed1994

Behavioral impairments of lead-injected young herring gulls in nature.

Lead is ubiquitous in the environment, and trace amounts enter the food chain and bioaccumulate in organisms high on the food chain. Although lead levels have been examined in a variety of wild species, effects data are usually from laboratory studies. Thus the relevance of effects to survival and fitness are not directly determined. In the field we compared the behavior of lead-injected young herring gulls (Larus argentatus) to the behavior of their control siblings who received an injection with no lead and to chicks from control nests that received no injections. Lead-injected chicks had significantly lower survival rates than all controls. Lead-injected chicks were less healthy than control chicks as measured by begging and walking scores and by the number of times they stumbled when walking. Control chicks had a higher degree of accuracy when pecking at their parents' bills to stimulate feeding compared to the lead-injected chicks. For all chicks, begging and walking scores improved with age. Behavioral deficits measured in the laboratory are homologous with those observed in the field.

Animals↗
PubMed1994

Heavy metal and selenium levels in feathers of known-aged common terns (Sterna hirundo).

Concentrations of five metals and selenium in the breast feathers of known-aged common terns (Sterna hirundo) were examined at a breeding colony in Massachusetts, USA. Concentrations of selenium, chromium, and manganese increased significantly with age among adults (2-21 years old), whereas concentrations of mercury, cadmium, and lead did not. Concentrations of cadmium, selenium and manganese were lower in fledglings (20-23 days old) than in adults. Concentrations of mercury, however, were higher in fledglings than in adults, and concentrations of chromium were higher in fledglings than in young adults, probably reflecting higher exposure to these metals in the breeding area than in the winter quarters where the adults' feathers were grown. At least for mercury, excretion of metals into the feathers at each molt was an efficient protective mechanism, preventing continued accumulation in the body with increasing age.

Aging↗
PubMed1994

Heavy metals in the hair of opossum from Palo Verde, Costa Rica.

Levels of lead, cadmium, mercury, chromium, and manganese were measured in the hair of opossum (Didelphis virginiana) from Palo Verde, Guanacaste, Costa Rica. This area has some agriculture, but is slated for extensive water development that will increase ecosystem exposure to a variety of agricultural chemicals. Metal levels were generally not intercorrelated except for chromium and lead, chromium and cadmium, and cadmium and lead. There were significant gender differences only for lead and chromium, with the significantly smaller females having higher levels. It is suggested that hair from mammals, particularly abundant ominivores may be useful, bioindicators of environmental quality over a long time period.

Animals↗