Po-Ya Chang

Lead poisoning caused by contaminated Cordyceps, a Chinese herbal medicine: two case reports

Two cases of lead poisoning, caused by the Chinese herbal medicine Cordyceps, were reported to the Department of Health in a laboratory-based blood lead surveillance program. Such unusual cases of lead poisoning have not been previously reported. These two patients took Cordyceps herbal medicine for treatment of underlying diseases. Loss of appetite and anemic signs of lead poisoning were manifested in one patient with a blood lead level of 130 microg/dl, while the other patient was asymptomatic with a blood lead level of 46 microg/dl. The lead content in the Cordyceps powder was found to be as high as 20 000 ppm. After cessation of intake in the asymptomatic patient, and cessation of intake and treatment with chelating agents in the symptomatic patient, the blood lead levels returned to normal range. This report raises concerns about lead poisoning from unusual herbal medicine worldwide.

Increased risk of preterm delivery among people living near the three oil refineries in Taiwan

The petrochemical and petroleum industries are two of the main sources of industrial air pollution in Taiwan. Data used in this study concern outdoor air pollution and the health of individuals living in communities in close proximity to oil refinery plants. The prevalence of delivery of preterm birth infants was significantly higher in mothers living near the oil refinery plants than in control mothers in Taiwan. After controlling for several possible confounders (including maternal age, season, marital status, maternal education, and infant sex), the adjusted odds ratio was 1.14 (95% CI=1.01-1.28) for delivery of preterm infants for mothers living near oil refinery plants. These data provide further support for the hypothesis that air pollution can affect the outcome of pregnancies.

Epidemiologic study of occupational injuries among foreign and native workers in Taiwan

This study was designed to compare the risk of occupational injuries in foreign workers compared to native workers in Taiwan. The cohort of foreign workers under study was constructed by records of legally registered workers migrated from foreign countries to Taiwan from July 1, 1991 to December 31, 1993. The native Taiwanese workers for comparison were labor-insured workers working in the same industries as foreign workers in 1992. The number of occupational injuries in the first year of employment were obtained by matching the cohort of foreign workers with the labor insurance payment records by name, birth date and passport number. The 1-year incidence rate of occupational injuries in the first year of employment was calculated and a standardized morbidity ratio (SMR) was used for comparison with adjustment for age distribution and to accommodate the small sample size of foreign workers. The risk to occupational injuries among total (SMR = 0.86) and male (SMR = 0.58) foreign workers was not higher; indeed, it was even lower, than that among native workers in Taiwan. However, the risk to female migrant workers, especially in the construction industry, was significantly higher than that of female Taiwanese workers (SMR = 1.60). Stratified by industry, the incidence was high in the fabricated metal products manufacturing industry and in machinery and equipment manufacturing industry for male foreign workers, while a high incidence for the female foreign workers occurred in construction industry and rubber products manufacturing industry. The risk of occupational injuries was greater for foreign workers who had been in Taiwan for only a short time. Most of the injuries occurred within the first 6 months of employment. Eighty-four out of the 394 occupational injuries among foreign workers resulted in disabilities. None of the accidents was fatal, but most of the disabilities were severe. The most common disabling injuries were cut or crushed fingers. The finding of a similar distribution of occupational injuries among foreign and native workers indicates that control measures are needed to reduce occupational injuries for all foreign and native workers in Taiwan.

Blood lead levels in the general population of Taiwan, Republic of China

The purpose of this study was to investigate the environmental lead exposure of the general population in Taiwan. A total of 2919 residents of Taiwan were selected by multistage sampling methods. The participants were characterized by questionnaires and 10 ml venous blood was collected for blood lead measurement. A quality assurance/quality control program was designed during the analysis of blood lead levels. The mean blood lead level of 2719 residents without occupational lead exposure was 8.29 ± 5.92 μg/dl. After adjustment for age and sex distribution to the Taiwan general population, the mean blood lead level was 8.10 μg/dl. Adjusted for an 11% underestimation of blood lead levels among the six laboratories, the mean blood lead level was estimated to be 8.99 μg/dl. This study also found that blood lead levels were associated with personal characteristics, i.e., gender, ethnic group, education level; lifestyle factors, i.e., smoking, alcohol consumption, sources of drinking water; and residential location, i.e., levels of urbanization, distance of house from the road. However, age, floor of residence, milk consumption, betel nut consumption, and Chinese herbal drug consumption were not found to be associated with blood lead levels. These results show that blood lead levels in Taiwan residents were not higher than in most developed and developing countries. Environmental lead pollution does not seem to be a serious problem in Taiwan.

Three-year survey of blood lead levels in 8828 Taiwanese adults

The purpose of this study was to investigate environmental lead exposure in the general Taiwanese population. A total of 8828 Taiwanese adults selected by a multistage sampling method were investigated. Characteristics of the participants were ascertained by questionnaire and 10 ml venous blood was drawn by public health nurses. The blood specimens were distributed to six laboratories for blood lead level (BLL) measurement. A quality control program was applied during the analysis of the BLLs in order to improve precision and accuracy. The arithmetic mean BLL of the 8828 Taiwanese adults was 7.70 ± 5.23 μg/dl, with a maximal level of 69.1 μ/dl. The median was 6.5 μ/dl and the 90th percentile was 14.0 μg/dl. After logarithmic transformation, the geometric mean was 1.84 ± 0.67 μg/dl. This study also found that elevated BLLs were associated with certain personal characteristics, i.e., gender, ethnic group, and education level; life-style factors, such as smoking, alcohol consumption, Chinese herbal drug consumption, milk consumption, and sources of drinking water; residential location, i.e., level of urbanization; and occupational history of lead exposure. However, age, floor level of residence, distance from house to road, and betel nut consumption were not associated with elevated BLLs. These results showed that BLLs in the Taiwanese population were not higher than those in developed and developing countries. Most of the influencing factors were also found in other studies; however, local factors such as ethnic group, Chinese herbal drug consumption, and sources of drinking water are important considerations in Taiwan when examining ways to prevent overexposure to lead in the general population.

Risk factors for high blood lead levels among the general population in Taiwan

Purpose: Environmental and occupational lead pollution is a common problem in both developing and industrialized countries. The purpose of this study is to evaluate the risk factors for high blood lead levels among the general population in Taiwan. Methods: After multi-stage sampling, we randomly selected 2803 subjects (1471 males and 1332 females) for this study. Univariate and multivariate logistic regression analyses were conducted to evaluate the risk of high blood lead. To control for differences in age and gender, all analyses were with age-adjusted and gender-stratified. Results: Among males, the mean age is 46 years (15 to 85 years), mean and median blood lead levels is 7.3 and 6.3μg/dl, respectively. Among females, the mean age is 43 years (15 to 84 years), mean and median blood lead level is 5.7 and 4.8μg/dl, respectively. Among males, the history of herbal drug use, drinking water from well or spring sources, and occupational lead exposure are significantly different between relatively high and normal blood lead level subjects. The history of occupational lead exposure, history of herbal drug use, and well or spring sources of drinking water are the major risk factors for high blood lead with odds ratio of 4.62 (95% CI: 2.82–7.55), 3.09 (95% CI: 1.60–5.97), 2.06 (95% CI: 1.13–3.76), and 2.37 (95% CI: 1.39–4.04), respectively. Among females, these characteristics remain important except the sources of drinking water. The history of herbal drug use and occupational lead exposure become the major risk factors for high blood lead with odds ratio of 2.94 (95% CI: 1.26–6.88) and 7.72 (95% CI: 3.51–16.99), respectively. In multivariate logistic regression analyses, we find that the risk factors for high blood lead in both genders include a history of herbal drug use and occupational lead exposure. Among males, the drinking water sources and factories in the neighboring areas are also significant factors for high blood lead. Conclusions: For the goal of reducing prevalence of high blood lead by the year 2000, the improvement and monitoring of the working environment, the careful attention to herbal drug use and the lead-free drinking water sources should be executed as thoroughly as possible to reduce the probability of lead pollution.

Reappraisal of the relation between blood lead concentration and blood pressure among the general population in Taiwan.

OBJECTIVES: The relation between blood lead concentration (PbB) and blood pressure was examined in a Taiwan nationwide population survey of PbB from July 1993 to June 1994. METHODS: After multistage sampling procedures, 2800 subjects (1471 males and 1329 females) with a mean (range) age of 44 (15-85) years were enrolled in this study. Anthropometric, blood pressure, and lifestyle factors were measured during household visits. The PbB was measured with a flameless atomic absorption spectrophotometer and all specimens were analysed in triplicate. RESULTS: The mean (range) PbB among all study subjects was 6.5 (0.1-69.1) micrograms/dl; among males it was 7.3 (0.1-69.1) micrograms/dl and among females 5.7 (0.1-40.1) micrograms/dl). The mean (range) systolic blood pressure among all subjects was 123 (80-210) mm Hg, among males it was 127 (80-200) mm Hg and among females 119 (80-210) mm Hg. The diastolic blood pressure among all subjects was 78 (40-150) mm Hg; among males it was 80 (40-130) mm Hg; and among females 75 (40-150) mm Hg. Age, body height, body weight, and body mass index (BMI) were significantly correlated with systolic blood pressure or diastolic blood pressure in both sexes. The PbB (or the natural logarithmic transformed PbB) was not significantly correlated with blood pressure among males or females. After adjustment for the potential confounders of age, age2, BMI, milk intake, alcohol consumption, and cigarette smoking, systolic blood pressure was significantly associated with PbB among males with a regression coefficient (beta) of 0.185 (p = 0.015). No significant association between PbB and blood pressure was found among females. CONCLUSIONS: From this study, only a weak association between systolic blood pressure and PbB was found among males. There was no strong evidence that PbB was a good predictor of blood pressure. However, the possibility that long term high body lead burden could cause high blood pressure could not be ruled out on the basis of this survey.

A study of noise-induced hearing loss and blood pressure in steel mill workers

SummaryA cross-sectional study on noise-induced hearing loss and blood pressure was conducted in a steel mill company. Three hundred testees were selected by cluster sampling. They were physically examined and an audiometry was done. Only 151 workers, who had the highest hearing threshold at 4000 Hz and without any family history of hypertension or treatment of drugs on cardiovascular troubles, were selected as subjects in this study. Multiple regression analyses revealed that body mass index, employment duration, age and hearing loss explained a significant amount of variation in systolic and diastolic blood pressure (R2 = 0.16 and 0.12, respectively). There was no significant relationship between hearing loss and blood pressure. In order to adjust confounding factors, analyses of covariances were used and the results suggest that hearing loss is unrelated to blood pressure. It seems that hearing loss is not appropriate as a noise exposure index to measure the relationship between noise exposure and blood pressure.

Aircraft Noise, Hearing Ability, and Annoyance

The relationship between aircraft noise, loss of hearing, and annoyance was explored in a study in two schools located near an international airport in Taiwan. Sixth-grade students (N = 242) were recruited from two schools and were classified into high- and low-noise-exposure groups, based on environmental noise measurements. Personal-equivalent 24-h noise exposure was measured to determine noise exposure at the individual level, and it was compared with hearing threshold level and with aircraft noise measured at the environmental level. Individual hearing threshold levels did not differ between environmental high- and low-noise-exposure groups, as evidenced by the lack of difference between the two groups for noise exposure measured at the individual level. However, the proportion of students who were annoyed by aircraft noise was higher in the environmental high-noise-exposure group, although personal 24-h noise exposure was not a factor for annoyance. The results indicated that environmental noise measurement was not an appropriate criterion for assessment of auditory damage (or noise-induced hearing loss) in Taiwan. As well, aircraft-noise exposure in Taiwan did not appear to affect the hearing threshold but nonetheless annoyed schoolchildren near the airport.

Effects of noise exposure and task demand on cardiovascular function

SummaryCardiovascular effects under various noise-exposure and task-demand conditions were studied among 40 senior highschool students. The subjects consisted of 20 males and 20 females with a mean age of 16.7 ± 0.7 years. All subjects had equivalent abacus performance ratings. Each subject was tested with a random sequence of six sessions. The time limit set for each session was 33 min. Six experimental sessions were constructed by a random combination of noise exposure (60, 85 or 90 dB (A)) white noise) and task demand (task presence or task absence) variables. Blood pressure measures were taken at the beginning and ending phases of each session. A task-demand variable was defined as a conjoint of mental arithmetic (3 min) and abacus arithmetic (30 min). The results from the present study show that the effect of noise exposure on task performance is remarkable. Only noise exposure tended to influence the performance of male students in abacus arithmetic. The effect of task demand on blood pressure was higher than that of noise exposure. No interaction effect (noise exposure × task demand) on blood pressure, was found via analyses of within-subjects two-way ANOVA.