Current Status of Genetically Engineered Pig to Monkey Kidney Xenotransplantation in Korea

BACKGROUND

In South Korea, pig-to-nonhuman primate trials of solid organs have only been performed recently, and the results are not sufficiently satisfactory to initiate clinical trials. Since November 2011, we have performed 30 kidney pig-to-nonhuman primate xenotransplantations at Konkuk University Hospital.

METHODS

Donor αGal-knockout-based transgenic pigs were obtained from 3 institutes. The knock-in genes were CD39, CD46, CD55, CD73, and thrombomodulin, and 2-4 transgenic modifications with GTKO were done. The recipient animal was the cynomolgus monkey. We used the immunosuppressants anti-CD154, rituximab, anti-thymocyte globulin, tacrolimus, mycophenolate mofetil, and steroids.

RESULTS

The mean survival duration of the recipients was 39 days. Except for a few cases for which survival durations were <2 days because of technical failure, 24 grafts survived for >7 days, with an average survival duration of 50 days. Long-term survival was observed 115 days after the removal of the contralateral kidney, which is currently the longest-recorded graft survival in Korea. We confirmed functioning grafts for the surviving transplanted kidneys after the second-look operation, and no signs of hyperacute rejection were observed.

CONCLUSIONS

Although our survival results are relatively poor, they are the best-recorded results in South Korea, and the ongoing results are improving. With the support of government funds and the volunteering activities of clinical experts, we aim to further improve our experiments and contribute to the commencement of clinical trials of kidney xenotransplantation in Korea.

Comparison of Graft Survival Between Full-Thickness and Lamellar Pig-to-Monkey Corneal Xenotransplantation from the Same Genetically Engineered Pig Model with Minimal Immunosuppression

BACKGROUND

The graft survival rate of full-thickness corneal xenotransplantation (XTP) with minimal immunosuppression in genetically engineered pigs is unknown, whereas lamellar corneal XTP shows satisfactory results. We compared graft survival between full-thickness and lamellar transplantations in the same genetically engineered pig.

METHODS

Six pig-to-monkey corneal transplantations were performed on 3 transgenic pigs. Two corneas harvested from 1 pig were transplanted into 2 monkeys using full-thickness and lamellar corneal xenotransplantation. The transgenic donor pigs used were α1,3-galactosyltransferase gene-knockout + membrane cofactor protein (GTKO+CD46) in one recipient and GTKO+CD46+ thrombomodulin (TBM) in the other.

RESULTS

The graft survival time for GTKO+CD46 XTP was 28 days. With the addition of TBM, the survival differences between lamellar and full-thickness XTP were 98 days versus 14 days and >463 days (ongoing) versus 21 days, respectively. An excessive number of inflammatory cells was observed in failed grafts, but none were in the recipient's stromal bed.

CONCLUSIONS

Unlike full-thickness corneal XTP, lamellar xenocorneal transplantation does not exhibit surgical complications, such as retrocorneal membrane or anterior synechia. The graft survival of lamellar XTP in this study was not as good as in our previous experiments, although the survival period was superior to that of full-thickness XTP. The difference in graft survival based on transgenic type is not definitive. Further studies using transgenic pigs and minimal immunosuppression need to focus on improving graft survival of lamellar XTP and using a larger sample size to determine the potential of full-thickness corneal XTP.

Caffeic acid phenethyl ester protects against photothrombotic cortical ischemic injury in mice

In this study, we aimed to investigate the neuroprotective effects of caffeic acid phenethyl ester (CAPE), an active component of propolis purified from honeybee hives, on photothrombotic cortical ischemic injury in mice. Permanent focal ischemia was achieved in the medial frontal and somatosensory cortices of anesthetized male C57BL/6 mice by irradiation of the skull with cold light laser in combination with systemic administration of rose bengal. The animals were treated with CAPE (0.5–5 mg/kg, i.p.) twice 1 and 6 h after ischemic insult. CAPE significantly reduced the infarct size as well as the expression of tumor necrosis factor-α, hypoxiainducible factor-1α, monocyte chemoattractant protein-1, interleukin-1α, and indoleamine 2,3-dioxygenase in the cerebral cortex ipsilateral to the photothrombosis. Moreover, it induced an increase in heme oxygenase-1 immunoreactivity and interleukin-10 expression. These results suggest that CAPE exerts a remarkable neuroprotective effect on ischemic brain injury via its anti-inflammatory properties, thereby providing a benefit to the therapy of cerebral infarction.

Development of a heat vulnerability index for New York State

OBJECTIVES

The frequency and intensity of extreme heat events are increasing in New York State (NYS) and have been linked with increased heat-related morbidity and mortality. But these effects are not uniform across the state and can vary across large regions due to regional sociodemographic and environmental factors which impact an individual's response or adaptive capacity to heat and in turn contribute to vulnerability among certain populations. We developed a heat vulnerability index (HVI) to identify heat-vulnerable populations and regions in NYS.

STUDY DESIGN

Census tract level environmental and sociodemographic heat-vulnerability variables were used to develop the HVI to identify heat-vulnerable populations and areas.

METHODS

Variables were identified from a comprehensive literature review and climate-health research in NYS. We obtained data from 2010 US Census Bureau and 2011 National Land Cover Database. We used principal component analysis to reduce correlated variables to fewer uncorrelated components, and then calculated the cumulative HVI for each census tract by summing up the scores across the components. The HVI was then mapped across NYS (excluding New York City) to display spatial vulnerability. The prevalence rates of heat stress were compared across HVI score categories.

RESULTS

Thirteen variables were reduced to four meaningful components representing 1) social/language vulnerability; 2) socioeconomic vulnerability; 3) environmental/urban vulnerability; and 4) elderly/ social isolation. Vulnerability to heat varied spatially in NYS with the HVI showing that metropolitan areas were most vulnerable, with language barriers and socioeconomic disadvantage contributing to the most vulnerability. Reliability of the HVI was supported by preliminary results where higher rates of heat stress were collocated in the regions with the highest HVI.

CONCLUSIONS

The NYS HVI showed spatial variability in heat vulnerability across the state. Mapping the HVI allows quick identification of regions in NYS that could benefit from targeted interventions. The HVI will be used as a planning tool to help allocate appropriate adaptation measures like cooling centers and issue heat alerts to mitigate effects of heat in vulnerable areas.

Cardioprotective Effect of the SDF-1α/CXCR4 Axis in Ischemic Postconditioning in Isolated Rat Hearts

BACKGROUND AND OBJECTIVES

Information about the role of the stromal cell-derived factor-1α (SDF-1α)/chemokine receptor type 4 (CXCR4) axis in ischemic postconditioning (IPOC) is currently limited. We hypothesized that the SDF-1α/CXCR4 signaling pathway is directly involved in the cardioprotective effect of IPOC.

METHODS

Isolated rat hearts were divided into four groups. The control group was subjected to 30-min of regional ischemia and 2-hour of reperfusion (n=12). The IPOC group was induced with 6 cycles of 10-second reperfusion and 10-second global ischemia (n=8) in each cycle. The CXCR4 antagonist, AMD3100, was applied before reperfusion in the IPOC group (AMD+IPOC group, n=11) and control group (AMD group, n=9). Hemodynamic changes with electrocardiography were monitored and infarct size was measured. The SDF-1α, lactate dehydrogenase (LDH) and creatine kinase (CK) concentrations in perfusate were measured. We also analyzed extracellular signal-regulated kinase 1/2 (ERK1/2) and Akt phosphorylation state expression.

RESULTS

IPOC significantly reduced infarct size, but AMD3100 attenuated the infarct reducing effect of IPOC. IPOC significantly decreased LDH and CK, but these effects were reversed by AMD3100. ERK1/2 and Akt phosphorylation increased with IPOC and these effects were blocked by AMD3100.

CONCLUSION

Based on the results of this study, SDF-1α/CXCR4 signaling may be involved in IPOC cardioprotection and this signaling pathway couples to the ERK1/2 and Akt pathways.

The effect of radiographic contrast media on reperfusion injury in the isolated rat heart

Background and Objectives

We investigated the effects of commonly used contrast media (CM) on myocardial ischemia-reperfusion injury in isolated rat hearts.

Subjects and Methods

Isolated rat hearts were subjected to 30 minutes of regional ischemia and 2 hours of reperfusion. The following CM (1 mL/1 L Krebs-Henseleit buffer) were randomly perfused for 15 minutes beginning 5 minutes before reperfusion and ending 10 minutes after reperfusion: iohexol (n=8), iopromide (n=8), ioversol (n=8), iomeprol (n=8), iopamidol (n=7), ioxaglate (n=8), and iodixanol (n=7). The effects of a direct bolus injection of undiluted iohexol, iopromide, or ioxaglate (each n=6) via the aortic root immediately prior to reperfusion were also evaluated. The area of necrosis, expressed as the percentage of the area at risk (AN/AR), and cardiodynamic variables were measured.

Results

The AN/AR of the control and experimental groups in the order described in methods was 33.7±6.4%, 30.3±7.4%, 34.7±12.6%, 29.2±10.2%, 20.9±7.6%, 22.6±8.7%, 18.8±7.9%, and 19.9±11.4%, respectively. Groups that received iomeprol and ioxaglate exhibited significantly decreased AN/AR values compared to those of control hearts (p=0.042 and p=0.013). No significant differences in the AN/AR were observed between control hearts and the groups injected with a single bolus of CM. No significant hemodynamic changes were noted after reperfusion among the groups.

Conclusion

The overall effects of the CM on coronary reperfusion were not deleterious, and better effects were noted in two CM groups. However, it is unclear whether this result was attributed to a specific physiochemical property of the CM.

Protein kinase C δ (PKCδ)-extracellular signal-regulated kinase 1/2 (ERK1/2) signaling cascade regulates glycogen synthase kinase-3 (GSK-3) inhibition-mediated interleukin-10 (IL-10) expression in lipopolysaccharide (LPS)-induced endotoxemia

Glycogen synthase kinase-3 (GSK-3) modulates a wide array of cellular processes, including embryonic development, cell differentiation, survival, and apoptosis. Recently, it was reported that a GSK-3 inhibitor attenuates lipopolysaccharide (LPS)-induced septic shock and regulates the mortality of endotoxemic mice. However, the detailed mechanism of reduced mortality via GSK-3 inhibition is not well defined. Herein, we showed that GSK-3 inhibition induces extracellular signal-regulated kinase 1/2 (ERK1/2) activation under LPS-stressed conditions via protein kinase C δ (PKCδ) activation. Furthermore, PKCδ-induced ERK1/2 activation by the inhibition of GSK-3 provoked the production of interleukin (IL)-10, playing a crucial role in regulating endotoxemia. Using a mitogen-activated protein kinase kinase-1 (MEK-1) and PKCδ inhibitor, we confirmed that GSK-3 inhibition induces PKCδ and subsequent ERK1/2 activation, resulting in increased IL-10 expression under LPS-treated conditions. We verified that septic shock caused by LPS is attenuated by GSK-3 inhibition using a GSK-3 inhibitor. This relieved endotoxemia induced by GSK-3 inhibition was restored in an ERK1/2-dependent manner. Taken together, IL-10 expression produced by GSK-3 inhibition-induced ERK1/2 activation via PKCδ relieved LPS-mediated endotoxemia. This finding suggests that IL-10 hyperexpression resulting from GSK-3 inhibition-induced ERK activation could be a new therapeutic pathway for endotoxemia.

Childhood asthma and indoor allergen exposure and sensitization in Buffalo, New York

This nested case-control study examined the association between prevalent asthma and indoor allergen sensitization and/or exposure among children (aged 5-17 years) in Buffalo, New York. The study included a self-administered questionnaire, clinical interviews, skin allergen sensitivity tests and home dust sampling for house dust mites, cat, dog, cockroach and mouse allergens. After adjusting for multiple confounders, asthma cases had higher odds of being sensitized to Der p dust mites (odds ratio [OR]=1.94, 95% confidence interval (CI): 1.13-3.35), cat (OR=1.96, 95% CI: 1.13-3.39), or dog allergens (OR=1.89, 95% CI: 1.10-3.22) than the controls. A significantly positive association between asthma status presence of cat allergen in the child's mattress (ORs: 2.61, 95% CI: 1.09-6.28) was also found. Children with both sensitization and environmental exposure to cat allergens had higher odds of asthma (OR=7.08, 95% CI: 2.12-23.62) than those who were only sensitized to cat allergen (OR=2.31, 95% CI: 1.01-5.32) or had only home exposures (OR=1.47, 95% CI: 0.47-4.65). The association between allergen sensitization and asthma was more consistent than for home exposures. The findings help to confirm the role of allergen sensitization and home exposure in regard to asthma, and suggest that both, individually and jointly, are associated with asthma.

Association between indoor mold and asthma among children in Buffalo, New York

Asthma is a leading chronic disease among children and places a significant burden on public health. Exposure to indoor mold has been associated with asthma symptoms. However, many mold assessments have relied on visual or other identification of damp conditions and mold presence, thus have not examined associations with specific fungal genera. The objective of this case-control study was to examine the relationship between airborne mold concentrations and asthma status among children and to identify the contribution from specific mold genera in air. Participants completed a questionnaire of home environmental conditions and underwent indoor air sampling in the home, from which viable and total-count fungal spores were quantified. The most prevalent fungi in the homes were the allergenic molds Cladosporium (98% and 87% of homes from viable and total count samples, respectively) and Penicillium (91% and 73%). There were no significant differences in mean fungal concentrations between the homes of cases and controls, although the observed rate of exposure to several molds was higher among the cases. Among children who lacked a family history of asthma, cases had significantly higher exposures to viable Aspergillus. Measured humidity levels in the home corresponded with some self-reported indicators of mold and dampness.

PRACTICAL IMPLICATIONS

The results of this study support existing literature that indoor fungal exposures play a role in current asthma status and that some qualitative assessments of mold exposure correspond to fungi present in indoor air.

Polycyclic aromatic hydrocarbons in soils and crops after irrigation of wastewater discharged from domestic sewage treatment plants

The effects of domestic wastewater application on the translocation and accumulation of polycyclic aromatic hydrocarbons (PAHs) in soil and crops (rice, lettuce, and barley) were investigated by Wagner's pot experiment. In the soils and crops after domestic wastewater irrigation, high-molecular weight PAHs (5 to 6 ring) were not detected, but low-molecular weight PAHs (3 to 4 ring) were only detected at trace levels.

Residential proximity to large airports and potential health impacts in New York State

OBJECTIVE

This study assessed whether residents living near commercial airports have increased rates of hospital admissions due to respiratory diseases compared to those living farther away from these airports.

METHODS

This cross-sectional study included all residents living within 12 miles from the center of each three airports (Rochester in Rochester, LaGuardia in New York City and MacArthur in Long Island). We obtained hospital admission data collected by the NYS Department of Health for all eligible residents who were admitted for asthma, chronic bronchitis, emphysema, chronic obstructive pulmonary disease and, for children aged 0-4 years, bronchitis and bronchiolitis during 1995-2000. Exposure indicators were distance from the airport (< or =5 miles versus >5 miles) and dominant wind-flow patterns from the airport (>75th percentile versus < or =75th percentile), as well as their combinations.

RESULTS

Increased relative risks of hospital admissions for respiratory conditions were found for residents living within 5 miles from the airports (1.47; 95% CI 1.41, 1.52 for Rochester and 1.38; 95% CI 1.37, 1.39 for LaGuardia) compared to those living >5 miles. We did not find positive associations between wind-flow patterns and respiratory hospital admissions among the residents in any airport vicinity. No differences were observed for MacArthur airport using either exposure measure.

CONCLUSION

There is the suggestion that residential proximity to some airports may increase hospital admissions for respiratory disorders. However, there are many factors that could influence this association that may differ by airport, which should be measured and studied further.

A comparison of self-reported hearing loss and audiometry in a cohort of New York farmers

The New York State Farm Family Health and Hazard Surveillance was conducted to assess the health status and safety practices among year-round adult farmers and farm residents in New York State and included a telephone interview survey of 1,727 persons from 552 farms. To determine the extent to which self-reported hearing loss is in agreement with audiometry, a subset of 376 participants who completed a hearing loss interview and pure-tone audiometry was analyzed. Thirty-six percent of the participants had self-reported hearing loss, defined as at least some difficulty hearing in one or both ears. The prevalence of audiometric hearing impairment, defined as a threshold average greater than 25 dB hearing level, was 9% for the binaural low-frequency average (500, 1000, and 2000 Hz), 29% for the binaural mid-frequency average (1000, 2000, 3000, and 4000 Hz), and 47% for the binaural high-frequency average (3000, 4000, 6000, and 8000 Hz). Agreement between self-report and audiometry was highest for the binaural mid-frequency average (kappa statistic 55%, sensitivity 77%, and specificity 82%). Self-reported hearing loss was found to be a moderately good measure of hearing impairment. We conclude that a simple questionnaire focusing on hearing difficulty is a useful and valid tool for conducting epidemiologic studies of farmers. Whenever possible, a substudy using audiometry should be conducted.

The association between local fish consumption and DDE, mirex, and HCB concentrations in the breast milk of Mohawk women at Akwesasne

A study was conducted to assess the extent to which the consumption of local fish contaminated with p,p'-dichlorodiphenyl dichloroethylene (p,p'-DDE), mirex, and hexachlorobenzene (HCB) has impacted the concentrations of these compounds in the milk of nursing Mohawk women residing along the St. Lawrence River. From 1986 to 1992, 97 Mohawk women were interviewed, and each donated a one-time sample of at least 50 ml of breast milk. The comparison population consisted of 154 Caucasians from other rural areas in New York State. After adjustment for potential confounders, Mohawk mothers who gave birth from 1986 to 1990 had significantly higher geometric mean p,p'-DDE milk concentrations than did the control group, but no significant differences were observed from 1991 to 1992. In contrast, mirex was significantly elevated among the Mohawks throughout the study period, while HCB showed no difference at any point. Mohawk women with the greatest estimated cumulative lifetime exposure to p,p'-DDE from local fish consumption had a significantly higher geometric mean milk level of that compound relative to control women, but no differences in mirex or HCB concentrations in breast milk by local fish consumption were found. The reduction in breast milk p,p'-DDE concentrations among the Mohawk women from 1986 to 1990 parallels a corresponding decrease in local fish consumption, and may be the result of the advisories that have been issued over the past decade recommending against the consumption of local fish by pregnant and nursing Mohawk women. Elevations in the concentrations of mirex in the breast milk of the Mohawks are consistent with the fact that it is a common contaminant in the region and throughout the Lake Ontario-St. Lawrence River Basin.

Predictors of hearing loss in New York farmers

BACKGROUND

Data from the telephone interview portion of the New York Farm Family Health and Hazard Surveillance were used to study self-reported hearing loss in New York farmers.

METHODS

One thousand six hundred and twenty-two persons completed the hearing loss and noise exposure interview. Hearing loss was defined as at least some trouble hearing in one or both ears. Predictors of hearing loss were determined using logistic regression.

RESULTS

Twenty-two percent of participants reported hearing loss. From the logistic regression, significant confounders are age (P = 0.0001), gender (P = 0.0001), being from a livestock farm (P = 0.012), and loss of consciousness due to head trauma (P = 0.04). Significant noise exposures are more hours of lifetime exposure to noisy farm equipment (P = 0.001) and having had a noisy non-farm job (with some hearing protection P = 0.002, without any hearing protection P = 0.0001).

CONCLUSIONS

Farm noise exposure is a serious risk to the hearing of this population. Although use of hearing protection should be encouraged, replacing and modifying farm equipment to decrease noise at the source should be the first priority.

Severe farm injuries among New York farmers

BACKGROUND

Data from the telephone interview portion of the New York State Farm Family Health and Hazard Surveillance were used to study the incidence and predictors of severe farm injury.

METHODS

One thousand seven hundred and six participants completed two telephone interviews in which they reported all injuries over a 12-month period.

RESULTS

Nine percent of participants reported at least one severe farm injury. Using logistic regression the significant risk factors for sustaining at least one severe farm injury are younger age, the presence of hearing loss or joint trouble, working more hours per day, being the owner/operator of the farm, and being from a farm with higher gross sales.

CONCLUSIONS

There needs to be continuing education of all farmers as to the risks of injury. However, when resources are limited, we recommend that injury education and interventions in this farming population should target younger farmers, those who work longer hours, owner/operators, farmers from higher grossing farms, with special attention to farmers who have physical impairments.

Fingerprinting PCB patterns among Mohawk women

This study examined the association of contaminated fish consumption and polychlorinated biphenyl (PCB) body burden by comparing the similarity of the congener pattern in yellow perch, caught near the point source of industrial pollution, and in other local fish to the pattern found in the breast milk of Mohawk women from Akwesasne, a Native American community located along the St. Lawrence River in New York, Ontario, and Quebec. The similarity is defined by the weighted Euclidean distance between two congener patterns. Ninety-seven Mohawk mothers participated and provided samples of breast milk. One hundred fifty-four nursing women from the Supplemental Nutrition Program for Women, Infants and Children (WIC) of Warren and Schoharie counties, New York, who gave birth during the same time period, were used as the comparison group. Results revealed that the breast milk of the Mohawk women, who ate the most local fish, had a congener pattern that more closely resembled that of perch caught near the waste site or average sampled fish caught in the Reserve than Mohawk women who ate less fish or the controls. The outcome demonstrates how PCBs may be "fingerprinted" as they migrate offsite from industrial sources and ultimately result in human exposure.

Hearing conservation for farmers: source apportionment of occupational and environmental factors contributing to hearing loss

Those who work on farms continue to have a strikingly high prevalence of hearing loss, despite efforts to promote hearing conservation in agriculture. To develop improved hearing conservation programs, we performed a source apportionment analysis for hearing loss in a large, multiphasic health survey, the New York Farm Family Health and Hazard Survey. We used information from audiometric, otoscopic, and tympanometric examinations; detailed general health and farm exposure interviews; and a second interview that focused on additional potential determinants of hearing loss. Hearing loss on audiometry was significantly associated with increased age, male gender, education through high school or less, lifetime years of hunting with guns, lifetime years of use of a grain dryer, and a history of spraying crops during the previous year. Hearing conservation programs for farmers should thus be directed toward reduction in noise exposure, both from occupational and non-occupational sources. Additional study is needed to evaluate the association seen between crop spraying and hearing loss.

Safety awareness among New York farmers

BACKGROUND

This study was conducted to assess the health status and safety practices among year-round adult farm workers and residents and included a telephone interview survey of 1,727 persons from 552 farms.

METHODS

Logistic regression was used to analyze four safety questions.

RESULTS

Among 541 farm owner/operators significant predictors of making substitutions in the use of chemicals and major changes to equipment include younger age, more persons assisting on the farm, and higher gross sales. Having training is associated with having more than a high school education. Among all participants the perception that personal protective equipment are useful is associated with being younger, male, an owner/operator or worker, and having at least a high school education.

CONCLUSIONS

These findings suggest that older and less educated farmers should be targeted for health and safety programs.

Asthma hospitalization rates and socioeconomic status in New York State (1987-1993)

This study examined the geographic distribution of asthma hospitalizations in New York State (NYS) and its association with socioeconomic status. Statewide asthma hospitalization data (1987-1993) were merged with 1990 census data by residential zip code. The asthma hospitalization rate increased in NYS from 1987 (2.54 per 1000) through 1993 (2.87 per 1000) and the increase is largely attributable to increases for children 4 years old and younger. The risk factors for asthma admission varied in different areas. However, rates of hospitalization because of asthma were generally higher in the zip codes areas with higher proportions of poverty, unemployment, poorly educated residents, African-Americans, and Hispanics.

Assessing environmental exposure to PCBs among Mohawks at Akwesasne through the use of geostatistical methods

The Mohawk Nation at Akwesasne is a Native American community located along the St. Lawrence River in New York State, Ontario, and Quebec. One component of a multiphase human health study was to assess the impact of different pathways of human exposure resulting from the off-site migration of polychlorinated biphenyl (PCB) contamination in this area. This paper illustrates how mapped residential information and environmental sampling data can be united to assist in exposure assessment for epidemiologic studies using geographic information system (GIS) technology and statistical methods. A proportional sampling scheme was developed to collect 119 surface soils. Using a method of cross validation, the average estimated error can be computed and the best estimator can be selected. Seven spatial methods were examined to estimate surface soil PCB concentrations; the lowest relative mean error was 0.42% for Inverse 3 nearest neighbor weighted according to the inverse distance, and the highest relative mean error was 4.4% for Voronoi polygons. Residual plots indicated that all methods performed well except near some of the sampling points that formed the outer boundaries of the sampling distribution.

Local fish consumption and serum PCB concentrations among Mohawk men at Akwesasne

A study was conducted to assess local fish consumption patterns and their relationship to concentrations of total polychlorinated biphenyls (PCBs) in the serum of Mohawk men residing near three hazardous waste sites. From 1992 to 1995, 139 men were interviewed and donated a 20-ml venous blood sample. The results indicated that the men ate a mean of 21.2 local fish meals during the past year, compared with annual means of 27.7 meals 1-2 years before and 88.6 meals more than 2 years before (P<0.001 for test of trend). This change is probably a consequence of advisories issued against the consumption of local fish, since 97% of the men were aware of the advisories and two-thirds had changed their behavior as a result. Multiple regression analysis revealed that serum PCB levels increased with age (beta=0.036, P<0.001) and local fish consumption (beta=0.088, P=0.006). The data suggest that local fish consumption has contributed to body burdens in this population and that the advisories have been effective in modifying local fish consumption habits.

Fish consumption and breast milk PCB concentrations among Mohawk women at Akwesasne

A study was conducted to determine the relation between the consumption of contaminated local fish and concentrations of total polychlorinated biphenyls (PCBs) and 68 PCB congeners in the milk of nursing Mohawk women residing near three hazardous waste sites. From 1986 to 1992, 97 Mohawk women were interviewed and donated at least 50 ml of breast milk. The comparison population consisted of 154 Caucasians. After adjustment for potential confounders, Mohawk mothers who gave birth in 1986-1989 had a geometric mean milk total PCB concentration of 0.602 ppm (fat basis) compared with 0.375 ppm for the control group (p = 0.009). These Mohawk women also had significantly higher geometric mean concentrations of nine congeners. Beginning in 1990, however, there were no significant differences between the Mohawk women and the comparison group. Estimated cumulative lifetime exposure from local fish consumption was significantly related to milk total PCB and to three congeners only among those Mohawks who gave birth from 1986 to 1989. The reduction in breast milk PCB concentrations parallels a corresponding decrease in local fish consumption and may be the result of the advisories that have been issued over the past decade recommending against the consumption of local fish by pregnant and nursing Mohawk women.

Does paternal occupational lead exposure increase the risks of low birth weight or prematurity?

The relation between paternal occupational lead exposure and low birth weight/prematurity was examined in a retrospective cohort study. Birth weight and gestational age (1981-1992), obtained from New York State birth certificates, were compared between lead-exposed and nonexposed workers. The exposed group (n = 4,256) consisted of births to male workers of reproductive age reported to the New York State Heavy Metals Registry. The control group (n = 2,318) consisted of the offspring of a random sample of male bus drivers, frequency matched by age and residence. There were no statistically significant differences in birth weight or gestational age between the exposed and the control groups. However, workers who had elevated blood lead levels for more than 5 years had a higher risk of fathering a child with low birth weight (risk ratio = 3.85, 95% confidence interval 1.5-9.88) or prematurity (risk ratio = 2.45, 95% confidence interval 1.03-5.84) than did controls after adjustment for paternal age, low maternal education, race, residence, gravidity, maternal spontaneous abortion history, perinatal complications, adequacy of prenatal care, and infant gender. The risks of low birth weight and prematurity increased with the duration of exposure to lead. Our results were limited by the inability to control for some potential confounders, such as pregravid underweight and maternal nutrition status.

Fertility rates among lead workers and professional bus drivers: a comparative study

We examined the relationship between lead exposure and fertility among men in a retrospective cohort study. Fertility (1981-1992) of lead-exposed workers was determined from birth certificate information and was compared with that of nonexposed workers. The exposed group consisted of 4256 reproductive-age male workers reported to the New York State Heavy Metals Registry. The comparison group consisted of a random sample of male bus drivers licensed in the state of New York; these men were frequency-matched by age and residence to the men who were exposed to lead. The actual number of births among lead workers was lower than the expected number of births for that group (standardized fertility ratio [SFR] = 0.88; 95% confidence interval [CI] = 0.81-0.95), especially among those who had elevated blood lead levels for longer than 5 years (SFR = 0.43; 95% confidence interval [CI]: = 0.31, 0.59). Even after adjusting for age, race, education, and residence, workers with > 5 years of exposure had reduced likelihood of fathering a child than those with a shorter period of exposure (relative risk, 0.38; 95% CI: 0.23, 0.61). Our study indicates that men with a long duration of lead exposure might have reduced fertility.

Polychlorinated biphenyl (PCB) and dichlorodiphenyl dichloroethylene (DDE) exposure among Native American men from contaminated Great Lakes fish and wildlife

The New York State Department of Health is performing an investigation of Mohawk men, women, and infants who live at the Akwesasne Reserve along the St. Lawrence River in New York, Ontario, and Quebec Three large industrial facilities bordering the Akwesasne Reserve have seriously contaminated the soil and the sediments and fish of the adjacent St. Lawrence River with polychlorinated biphenyls (PCBs). The main study goals are to investigate the associations among the consumption of locally caught fish, residential exposure, body burdens of PCBs, and liver enzyme induction. Contamination with PCBs, polychlorinated dibenzofurans, polychlorinated dibenzodioxins, polyaromatic hydrocarbons, dichlorodiphenyl dichloroethylene (DDE) and other chemicals has been documented in locally caught fish, ducks, and other wildlife. The contamination of fish and wildlife is a major concern of the Mohawk people, since their tradition and culture emphasize the interdependence of man and his environment and because many residents formerly depended heavily on local fish and waterfowl for food. The focus of this research from 1986-1992 was on nursing women and infants. The major purpose of the current project is to determine if there are associations between dietary, residential, and occupational exposures to PCBs and DDE and individual body burdens in Mohawk men, specifically the husbands, partners, fathers, brothers, or other male relatives of the women in our other studies. In other fish-eating populations, adult men have tended to demonstrate higher PCB and DDE body burdens than women and children. Exposure estimates based on the reported consumption of locally caught fish and wildlife and residential histories will be correlated with the specific pattern of PCB congeners found in serum, thereby establishing a direct relationship between two potential sources of exposure and body burdens. Liver function will be examined through the caffeine breath test (CBT), a sensitive, noninvasive method of assessment of enzyme induction, one of the earliest detectable biological responses to PCBs in laboratory animals. This test appears promising as a method to detect subtle subclinical effects before the onset of overt clinical symptoms. The project is among the first to explore differences in dietary and other exposures, body burdens, and potential adverse health effects due to specific PCB congeners in men and women from the same source population.

Fluoride exposure and childhood osteosarcoma: a case-control study

OBJECTIVES

This study tests the hypothesis that fluoride exposure in a nonoccupational setting is a risk factor for childhood osteosarcoma.

METHODS

A population-based case-control study was conducted among residents of New York State, excluding New York City. Case subjects (n = 130) were diagnosed with osteosarcoma between 1978 and 1988, at age 24 years or younger. Control subjects were matched to case subjects on year of birth and sex. Exposure information was obtained by a telephone interview with the subject, parent, or both.

RESULTS

Based on the parents' responses, total lifetime fluoride exposure was not significantly associated with osteosarcoma among all subjects combined or among females. However, a significant protective trend was observed among males. Protective trends were observed for fluoridated toothpaste, fluoride tablets, and dental fluoride treatments among all subjects and among males. Based on the subjects' responses, no significant associations between fluoride exposure and osteosarcoma were observed.

CONCLUSIONS

Fluoride exposure does not increase the risk of osteosarcoma and may be protective in males. The protective effect may not be directly due to fluoride exposure but to other factors associated with good dental hygiene. There is also biologic plausibility for a protective effect.

Mortality among New York State highway maintenance workers: 1958-1980

The mortality profile of 9585 male New York State Department of Transportation (NYSDOT) highway maintenance workers was examined by calculating age-era standard mortality ratios (SMRs), using the general male population of upstate New York as a reference group, for the period 1958-1980. The SMR for all workers was 1.14 (95% CI = 1.09, 1.18), with the greatest all-cause mortality among laborers (SMR = 1.23, 95% CI = 1.16, 1.29). The major contributors to this increase among laborers were circulatory system diseases (SMR = 1.18, 95% CI = 1.10, 1.27), diseases of the respiratory system (SMR = 1.34, 95% CI = 1.09, 1.64), digestive system diseases (SMR = 1.57, 95% CI = 1.26, 1.94), genitourinary system diseases (SMR = 1.61, 95% CI = 1.02, 2.41) and accidents, poison, and violence (SMR = 1.44, 95% CI = 1.19, 1.74). Some of the elevated risks observed may be attributed to cigarette smoking and other life-style factors that could not be assessed with the data available. However, the mortality risks for laborers increased with length of employment and latency, suggesting that occupational exposures may be contributing to the elevated risk in this cohort. Further studies should include information on life-style variables and other confounders as well as more detail on specific occupational exposures.

Fish PCB concentrations and consumption patterns among Mohawk women at Akwesasne

A study was conducted to determine concentrations of polychlorinated biphenyls (PCBs) in local fish and to establish patterns of fish consumption of nursing Mohawk women residing near three industrial hazardous waste sites. From 1986 to 1992, 97 Mohawk women were interviewed within one month postpartum. A comparison group consisted of 154 nursing Caucasians. Samples of 348 local fish were analyzed for PCBs. The results indicated that fish in the Mohawk area, especially those collected offshore from the waste sites, had been contaminated with PCBs. The dietary data showed a greater past prevalence of local fish consumption among Mohawk mothers, with an overall annual mean of 23.5 local fish meals more than one year before the pregnancy compared with 14.1 for the control women (p < 0.001). The prevalence of consumption by the Mohawks, however, declined over time, resulting in overall mean rates of 9.2 local fish meals one year or less before pregnancy, and 3.9 meals per year during pregnancy (p < 0.001 for linear trend). Compared to the Mohawks, significantly fewer control women stopped eating local fish, and their rates declined less sharply. A secular trend was also observed in the overall rate of consumption during pregnancy for the Mohawks, with those who gave birth in 1986-1989 having a mean of 10.7 local fish meals per year during pregnancy, compared with means of 3.6 and 0.9 respectively for women who delivered in 1990 and 1991-1992 (p < 0.05 for linear trend). No such trend was apparent for the controls. No background variable was significantly related to the rate of local fish consumption among the Mohawks, but a decrease over time in the rate of local fish consumption was greater among those Mohawks who ate the most local fish initially (r = -0.76, p < 0.001), or who also reduced their alcohol intake during pregnancy (r = 0.35, p < 0.05). Mohawks were also more likely than the controls to trim the fat, remove the skin from, and fry and fish they ate during the past year. These dietary changes may be the result of advisories that have been issued over the past decade recommending against the consumption of local fish by pregnant and nursing Mohawk women. Such changes, if sustained, should reduce their exposure to PCBs and correspondingly the potential for adverse health effects.

Mono-ortho- and non-ortho-substituted polychlorinated biphenyls in human milk from Mohawk and control women: effects of maternal factors and previous lactation

Fifty-four individual human milk samples from 50 mothers (20 Mohawks and 30 controls) were analyzed for four non-ortho- and eight mono-ortho-substituted polychlorinated biphenyls (PCBs). Mean total coplanar PCBs concentrations were 49 ng/g and 55 ng/g lipid for Mohawk and control women, respectively. A statistical evaluation of all analytical data reveals no significant difference of total coplanar PCB level between Mohawk and control women. The level of these contaminants is influenced by the age of the mother, number of breastfed children, and length of nursing period. Older women, primiparae, and cigarette smokers had higher levels of coplanar PCBs. In general, women had higher levels of coplanar PCBs in the first lactation and in the earlier samples of a given lactation, while levels declined both with duration of breast-feeding and with number of children nursed. The contribution of individual non-ortho- and mono-ortho-substituted PCB congeners to the total calculated toxic equivalent values (sigma TEQ) was assessed for the breast milk samples. The levels of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in human milk of pooled specimens from Los Angeles, California and Binghamton, New York, widely separate cities in the United States (Schecter et al. 1989), were presented for reference purpose. The main contributions to the sigma TEQ were PCB congeners #118 (25.8 pg/g lipid), #126 (25 pg/g lipid), #105 (10.8 pg/g lipid), and #156 (7.4 pg/g lipid). Collectively, these compounds accounted for 70% of the sigma TEQ values.(ABSTRACT TRUNCATED AT 250 WORDS)

Exposure to asbestiform minerals and radiographic chest abnormalities in a talc mining region of upstate New York

A radiologist in New York reported a high prevalence of pulmonary fibrosis in St. Lawrence and Jefferson counties. The New York State Department of Health responded by conducting a case history study of radiographic abnormalities found in the lung parenchyma and pleura of residents in Lawrence and Jefferson counties, where tremolitic talc has been mined for many years. During a 1-y period, all radiographs from 6 hospitals in the region were reviewed. A B-reader confirmed that 355 of 9,442 patients who were at least 40 y of age (3.8%) had a relevant abnormality; 60% of them reported occupational exposure to asbestiform minerals, and another 15% had a chest condition or injury that could have accounted for the abnormal radiograph. The results should be interpreted cautiously, but there was no evidence of widespread radiographic abnormalities resulting from ambient dust exposure. The data, however, support earlier studies that indicate that talc miners and millers experience excess parenchymal fibrosis and pleural changes. The data also suggest that individuals in the paper industry and construction trades may be at risk.