Biomedical subjects

S A Hwang

Publications and source records attributed to S A Hwang.

At least 19 recordsLinked to original sources

PubMed2001

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.

Adult↗

PubMed2001

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.

Adult↗

PubMed2001

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.

Adult↗

PubMed2000

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.

Adult↗

PubMed2000

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.

Adult↗

PubMed1999

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.

Adolescent↗

PubMed1999

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.

Environmental Exposure↗

PubMed1999

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.

Adolescent↗

PubMed1998

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.

Adult↗

PubMed1998

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.

Adult↗

PubMed1996

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.

Adult↗

PubMed1995

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.

Adult↗

PubMed1995

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.

Adolescent↗

PubMed1994

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)

Adolescent↗

PubMed1993

A case-control study of malignant melanoma of the trunk among white males in upstate New York.

To address the increase in the incidence of cutaneous melanoma in upstate New York in recent decades, a case-control study was conducted of the constitutional and environmental risk factors for malignant melanoma of the trunk among white males. Cases were identified from the New York Cancer Registry from 1977 through 1979 (the period of the greatest relative increase in incidence), and controls were selected using random digit dialing methods. A total of 324 cases or their next-of-kin and 415 controls were interviewed regarding physical and sociodemographic characteristics, lifestyle habits, and medical histories. The following variables were statistically significant in the final logistic regression analysis: birthmarks (O.R. = 3.87); sunburn easily (O.R. = 1.83); fair skin tone (O.R. = 1.63); northern European ancestry (O.R. = 1.51); blue eye color (O.R. = 1.46); and participation in water sports (O.R. = 2.02). Interaction terms between constitutional and environmental variables resulted in a significant relationship between the presence of freckles and bathing two or more times per day. Among freckled individuals, those who bathed more than once per day had a sixfold elevation in the risk compared to those who bathed less often. In comparison, the odds ratio for frequent bathing among men without freckles was only 1.24. The data suggest the following hypothesis for further study: the possibility that frequent bathing may be deleterious, especially among freckled individuals or those with pigmented nevi.

Case-Control Studies↗

PubMedDate not supplied

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.

Animals↗

PubMedDate not supplied

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.

Adult↗

PubMedDate not supplied

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.

Adult↗