A 2-day short-term bioassay, using prepubertal female Sprague-Dawley rats, was developed to study... more A 2-day short-term bioassay, using prepubertal female Sprague-Dawley rats, was developed to study effects of polychlorinated biphenyls (PCBs) on hepatic enzyme induction, uterotropic responses, and thyroid hormone levels. Three approaches have been used to study the multiple effects of PCB mixtures: (1) environmental mixtures (soil, dust and air samples) collected from the Sangamo landfill site were directly examined and the chemical compositions of these mixtures were analyzed; (2) the soil extract from the Sangamo landfill site was fractionated by alumina-charcoal column chromatography, the effects of this fraction were tested, and the results were compared with the effects of the original soil extract; (3) a combination of specific chlorobiphenyls (CBs) (2,3,3$\sp\prime,4\sp\prime$,6-pentachlorobiphenyl (CB 110) plus 3,3$\sp\prime,4,4\sp\prime$,5-pentachlorobiphenyl (CB 126)) and a synthetic mixture which contained 95.5% CB 110, 0.5% CB 126 and 4% two unidentified pentaCBs were also examined. In addition, the effects of 3 environmentally abundant di-ortho CBs (2,2$\sp\prime,4,4\sp\prime,5,5\sp\prime$-hexachlorobiphenyl (CB 153), 2,2$\sp\prime$,5-trichlorobiphenyl (CB 18) and CB 110) were examined.None of the 3 individual CBs induced P4501A activity, whereas CB 153 and CB 110 markedly induced P4502B activity. All 3 CBs produced uterotropic responses at least at one or more of the doses tested. CB 153 was the most estrogenic of the 3 CBs tested. All 3 CBs slightly reduced serum total thyroxine (T$\sb4$) in prepubertal rats, but these reductions were not statistically significant at up to 120 mg/kg. In addition, the level of serum CB residues in prepubertal rats was considerable higher than would be expected of adult rats at similar doses.All PCB mixtures studied were able to induce both P4501A and 2B activities as well as 4-nitrophenol UDP glucuronosyltransferase (4-NP UDPGT) activity. All mixtures examined effectively depressed serum total T$\sb4$ to less than 50% of controls at higher doses and dose:response relationships were very similar despite significant differences in proportions of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-like compounds and non-TCDD-like compounds in the mixtures. The mixtures containing lower proportions of TCDD-like compounds (such as the air extract collected from the Sangamo landfill site and the charcoal-filtered soil extract) were more estrogenic than the mixtures containing greater amounts of TCDD-like compounds. Some antagonistic effects were observed in P450 enzyme activity as well as uterotropic responses between the mixtures containing TCDD-like compounds and non-TCDD-like compounds. These results indicate that both TCDD-like and non-TCDD-like effects of PCBs should be considered in assessing the potential hazards of environmental PCB mixtures.U of I OnlyETDs are only available to UIUC Users without author permissio
A 2-day short-term bioassay, using prepubertal female Sprague-Dawley rats, was developed to study... more A 2-day short-term bioassay, using prepubertal female Sprague-Dawley rats, was developed to study effects of polychlorinated biphenyls (PCBs) on hepatic enzyme induction, uterotropic responses, and thyroid hormone levels. Three approaches have been used to study the multiple effects of PCB mixtures: (1) environmental mixtures (soil, dust and air samples) collected from the Sangamo landfill site were directly examined and the chemical compositions of these mixtures were analyzed; (2) the soil extract from the Sangamo landfill site was fractionated by alumina-charcoal column chromatography, the effects of this fraction were tested, and the results were compared with the effects of the original soil extract; (3) a combination of specific chlorobiphenyls (CBs) (2,3,3$\sp\prime,4\sp\prime$,6-pentachlorobiphenyl (CB 110) plus 3,3$\sp\prime,4,4\sp\prime$,5-pentachlorobiphenyl (CB 126)) and a synthetic mixture which contained 95.5% CB 110, 0.5% CB 126 and 4% two unidentified pentaCBs were also examined. In addition, the effects of 3 environmentally abundant di-ortho CBs (2,2$\sp\prime,4,4\sp\prime,5,5\sp\prime$-hexachlorobiphenyl (CB 153), 2,2$\sp\prime$,5-trichlorobiphenyl (CB 18) and CB 110) were examined.None of the 3 individual CBs induced P4501A activity, whereas CB 153 and CB 110 markedly induced P4502B activity. All 3 CBs produced uterotropic responses at least at one or more of the doses tested. CB 153 was the most estrogenic of the 3 CBs tested. All 3 CBs slightly reduced serum total thyroxine (T$\sb4$) in prepubertal rats, but these reductions were not statistically significant at up to 120 mg/kg. In addition, the level of serum CB residues in prepubertal rats was considerable higher than would be expected of adult rats at similar doses.All PCB mixtures studied were able to induce both P4501A and 2B activities as well as 4-nitrophenol UDP glucuronosyltransferase (4-NP UDPGT) activity. All mixtures examined effectively depressed serum total T$\sb4$ to less than 50% of controls at higher doses and dose:response relationships were very similar despite significant differences in proportions of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-like compounds and non-TCDD-like compounds in the mixtures. The mixtures containing lower proportions of TCDD-like compounds (such as the air extract collected from the Sangamo landfill site and the charcoal-filtered soil extract) were more estrogenic than the mixtures containing greater amounts of TCDD-like compounds. Some antagonistic effects were observed in P450 enzyme activity as well as uterotropic responses between the mixtures containing TCDD-like compounds and non-TCDD-like compounds. These results indicate that both TCDD-like and non-TCDD-like effects of PCBs should be considered in assessing the potential hazards of environmental PCB mixtures.U of I OnlyETDs are only available to UIUC Users without author permissio
Recently, investigators have reported bioaccumulation of polychlorinated biphenyls (PCBs) in inse... more Recently, investigators have reported bioaccumulation of polychlorinated biphenyls (PCBs) in insects collected at hazardous waste sites. Little is known about differences in bioaccumulation of particular PCB congeners in insects. The authors report on the toxicokinetics of a non-coplanar ortho substituted congener, 2,2',4,4'-tetrachlorobiphenyl (PCB-47) and a coplanar non-ortho substituted PCB, 3,3',4,4'-tetrachlorobiphenyl (PCB-77) in topically treated house crickets. Penetration and excretion were more rapid for PCB-47 than for PCB-77. PCB-47 demonstrated a high affinity for abdomen, gut, and gonads, whereas, PCB-77 had a greater affinity for the head and thorax. Sex differences were observed in excretion and distribution. Females had an increased excretion of PCBs and increased accumulation in gut and gonads compared to males. Differences in lipophilicity can explain differences in distribution between sexes and of compounds within sexes. However, to explain the observed difference in penetration, it is necessary to invoke explanations based on stearic factors associated with coplanarity of the molecules. Differences in excretion are likely related to sex differences in mixed-function oxidase activities. These toxicokinetic data suggest that the more toxic coplanar congener, PCB-77, is likely to be more persistent in crickets compared to PCB-47, despite its lower lipophilicity.
Fig. 3. Mean percentage cover (±SE) of algae and sessile animals on seawalls, breakwaters, and na... more Fig. 3. Mean percentage cover (±SE) of algae and sessile animals on seawalls, breakwaters, and natural rocky shores at the 2 ports sampled from autumn 2010 to summer 2011 (n = 10). In the same season, means with different letters indicate significant differences according to Student-Newman-Keuls test (p <0.05).
Fig. 1. Location of study sites. (A) Taiwan, (B) the northern coast of Taiwan, (C) Houcuo fishing... more Fig. 1. Location of study sites. (A) Taiwan, (B) the northern coast of Taiwan, (C) Houcuo fishing port, and (D) Linshanbi fishing port.
Fig. 2. Mean density (±SE) of mobile molluscs on seawalls, breakwaters, and natural rocky shores,... more Fig. 2. Mean density (±SE) of mobile molluscs on seawalls, breakwaters, and natural rocky shores, at Houcuo and Linshanbi fishing ports between autumn 2010 and summer 2011. In the same season, means with different letters indicate significant differences according to Student-Newman-Keuls test (p <0.05).
Fluctuating asymmetry (FA) is defined as small, random deviation from perfect bilateral symmetry ... more Fluctuating asymmetry (FA) is defined as small, random deviation from perfect bilateral symmetry of morphological trait and an increase of FA is proposed to be caused by genetic and environmental stress. In this study, measures of FA in the shore crab, Grapsus albolineatus, were used to investigate the impact of a municipal landfill on the surrounding coastal area of northern Taiwan based on a hypothesis that poor environmental conditions can increase degrees of FA. The majority of leg segments examined showed higher mean FA levels in crabs collected from Pa-Dor-Tze than those from either of the control sites. There were significant increases in FA levels in eleven of sixteen leg segments in crabs collected from Pa-Dor-Tze compared to those from Wai-Mon-San, and four of sixteen leg segments in crabs collected from Pa-Dor-Tze compared to those from Red-Ben. Furthermore, there were significant increases in eight of nine composite FA indexes in crabs collected from Pa-Dor-Tze compared ...
The interactions among climate change, air pollution, and human health are multiple and complex. ... more The interactions among climate change, air pollution, and human health are multiple and complex. Many epidemiological studies in Taiwan have consistently demonstrated the effects of short-term exposures to extreme weather events, particulate matter, and traffic-related air pollutants on a variety of health effects. However, these findings might not explain or predict overall seasonal mortality patterns to provide insights into the drivers of mortality acting on society levels for public health policy and practice. There are very limited studies on seasonality of weather, air pollution, and mortality in Taiwan. The objectives of this study are to evaluate if there are any changes in trends and seasonality of mortality in three major Taiwanese cities from 1991 to 2010 and examine its association with climatic condition and air pollution. Among these major Taiwanese cities, seasonal mortality patterns are similar in two subtropical cities, Taipei and Taichung, compared to another tropical city, Kaohsiung. Taipei had significantly increased trends in most monthly temperature variables and the number of hot days examined during 1991–2010 compared to the other two cities. Winter/summer ratios of mortality only showed a decreased trend in Taipei, but not in Taichung or Kaohsiung. Mean monthly ambient temperature was also found as the most optimal temperature variable for predicting all-cause monthly mortality at all three cities in this study. Seasonal mortality patterns in three cities were with higher levels of deaths from December to March. Trends in air quality are showing mixed patterns over the past two decades. SO2, CO, and NOx concentrations have decreased significantly and steadily, while O3 has significantly increased in recent years. In three major Taiwanese cities, O3 and PM10 are major air pollutants of current concerns. The results of this study showed that monthly mean O3, PM10, and NOx levels and monthly mortality were not closely related, but temperature-related variables were positively associated with monthly mortality among three major Taiwanese cities. Moreover, changes in other socioeconomic and demographic factors may also play a key role in determining seasonality mortality and morbidity and need to be considered in future studies.
Effects of climate change on human health become increasingly a growing concern. Especially, the ... more Effects of climate change on human health become increasingly a growing concern. Especially, the worldwide risk of vector-borne diseases, such as dengue fever, could be strongly influenced by meteorological conditions. Taiwan is unique in terms of its geographical location and abundant ecological environments. It makes Taiwan an unusual epidemic region for dengue disease. This chapter focuses on risk factors related to climate change and geographical characteristics which have been shown to affect dengue transmission in Taiwan. Empirical studies all concluded that relationship between temperature and dengue incidence is highly correlated. Some of studies also concluded that temperature increase has more dramatic influence to dengue incidences in southern Taiwan. However, the effects of other meteorological factors, including precipitation and humidity, on dengue incidence are rather inconsistent. Extreme weather events, such as heavy rainfall, would be possible to damage the habitat...
Polychlorinated biphenyls (PCBs) are considered potential endocrine disruptors due to their abili... more Polychlorinated biphenyls (PCBs) are considered potential endocrine disruptors due to their ability to act as estrogens, antiestrogens and goitrogens. The aim of this study is to ascertain whether acute postnatal treatment with 3,3 0 ,4,4 0 -tetrachlorobiphenyl (CB 77) affects sperm function and hormone levels in adult rats. Male Sprague–Dawley rats received CB 77 by ip injection of 2 or 20 mg/kg at day 21 and sacrificed at day 112. At day 112, right and left testis weights were significantly increased, whereas sperm count, motility, total motile sperm count, curvilinear velocity, average path velocity, straight-line velocity, and beat-cross frequency for motile sperm were significantly decreased in rats treated with 20 mg/kg CB 77. Sperm–oocyte penetration rate was significantly reduced in rats treated with either 2 or 20 mg/kg CB 77. There was high sperm acrosome reaction rate (ARR) in the 20 mg/kg CB 77-treated rats. There was a significant increase in thyroid-stimulating hormone...
Both social and natural environments have profound effects on human health. This paper attempts t... more Both social and natural environments have profound effects on human health. This paper attempts to present an overview of recent environmental health status and related studies conducting in Taiwan. First, temporal trends of environmental health status in Taiwan are described. Then, regional variations of environmental health in Taiwan are discussed. Finally, different studies on relationships between human health and environment in Taiwan are introduced and examined. More work still needs to be done in order to give a complete perspective on geographical dimensions of disease occurrence and health care to improve our health policy in different parts of Taiwan.
A 2-day short-term bioassay, using prepubertal female Sprague-Dawley rats, was developed to study... more A 2-day short-term bioassay, using prepubertal female Sprague-Dawley rats, was developed to study effects of polychlorinated biphenyls (PCBs) on hepatic enzyme induction, uterotropic responses, and thyroid hormone levels. Three approaches have been used to study the multiple effects of PCB mixtures: (1) environmental mixtures (soil, dust and air samples) collected from the Sangamo landfill site were directly examined and the chemical compositions of these mixtures were analyzed; (2) the soil extract from the Sangamo landfill site was fractionated by alumina-charcoal column chromatography, the effects of this fraction were tested, and the results were compared with the effects of the original soil extract; (3) a combination of specific chlorobiphenyls (CBs) (2,3,3$\sp\prime,4\sp\prime$,6-pentachlorobiphenyl (CB 110) plus 3,3$\sp\prime,4,4\sp\prime$,5-pentachlorobiphenyl (CB 126)) and a synthetic mixture which contained 95.5% CB 110, 0.5% CB 126 and 4% two unidentified pentaCBs were also examined. In addition, the effects of 3 environmentally abundant di-ortho CBs (2,2$\sp\prime,4,4\sp\prime,5,5\sp\prime$-hexachlorobiphenyl (CB 153), 2,2$\sp\prime$,5-trichlorobiphenyl (CB 18) and CB 110) were examined.None of the 3 individual CBs induced P4501A activity, whereas CB 153 and CB 110 markedly induced P4502B activity. All 3 CBs produced uterotropic responses at least at one or more of the doses tested. CB 153 was the most estrogenic of the 3 CBs tested. All 3 CBs slightly reduced serum total thyroxine (T$\sb4$) in prepubertal rats, but these reductions were not statistically significant at up to 120 mg/kg. In addition, the level of serum CB residues in prepubertal rats was considerable higher than would be expected of adult rats at similar doses.All PCB mixtures studied were able to induce both P4501A and 2B activities as well as 4-nitrophenol UDP glucuronosyltransferase (4-NP UDPGT) activity. All mixtures examined effectively depressed serum total T$\sb4$ to less than 50% of controls at higher doses and dose:response relationships were very similar despite significant differences in proportions of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-like compounds and non-TCDD-like compounds in the mixtures. The mixtures containing lower proportions of TCDD-like compounds (such as the air extract collected from the Sangamo landfill site and the charcoal-filtered soil extract) were more estrogenic than the mixtures containing greater amounts of TCDD-like compounds. Some antagonistic effects were observed in P450 enzyme activity as well as uterotropic responses between the mixtures containing TCDD-like compounds and non-TCDD-like compounds. These results indicate that both TCDD-like and non-TCDD-like effects of PCBs should be considered in assessing the potential hazards of environmental PCB mixtures.U of I OnlyETDs are only available to UIUC Users without author permissio
A 2-day short-term bioassay, using prepubertal female Sprague-Dawley rats, was developed to study... more A 2-day short-term bioassay, using prepubertal female Sprague-Dawley rats, was developed to study effects of polychlorinated biphenyls (PCBs) on hepatic enzyme induction, uterotropic responses, and thyroid hormone levels. Three approaches have been used to study the multiple effects of PCB mixtures: (1) environmental mixtures (soil, dust and air samples) collected from the Sangamo landfill site were directly examined and the chemical compositions of these mixtures were analyzed; (2) the soil extract from the Sangamo landfill site was fractionated by alumina-charcoal column chromatography, the effects of this fraction were tested, and the results were compared with the effects of the original soil extract; (3) a combination of specific chlorobiphenyls (CBs) (2,3,3$\sp\prime,4\sp\prime$,6-pentachlorobiphenyl (CB 110) plus 3,3$\sp\prime,4,4\sp\prime$,5-pentachlorobiphenyl (CB 126)) and a synthetic mixture which contained 95.5% CB 110, 0.5% CB 126 and 4% two unidentified pentaCBs were also examined. In addition, the effects of 3 environmentally abundant di-ortho CBs (2,2$\sp\prime,4,4\sp\prime,5,5\sp\prime$-hexachlorobiphenyl (CB 153), 2,2$\sp\prime$,5-trichlorobiphenyl (CB 18) and CB 110) were examined.None of the 3 individual CBs induced P4501A activity, whereas CB 153 and CB 110 markedly induced P4502B activity. All 3 CBs produced uterotropic responses at least at one or more of the doses tested. CB 153 was the most estrogenic of the 3 CBs tested. All 3 CBs slightly reduced serum total thyroxine (T$\sb4$) in prepubertal rats, but these reductions were not statistically significant at up to 120 mg/kg. In addition, the level of serum CB residues in prepubertal rats was considerable higher than would be expected of adult rats at similar doses.All PCB mixtures studied were able to induce both P4501A and 2B activities as well as 4-nitrophenol UDP glucuronosyltransferase (4-NP UDPGT) activity. All mixtures examined effectively depressed serum total T$\sb4$ to less than 50% of controls at higher doses and dose:response relationships were very similar despite significant differences in proportions of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-like compounds and non-TCDD-like compounds in the mixtures. The mixtures containing lower proportions of TCDD-like compounds (such as the air extract collected from the Sangamo landfill site and the charcoal-filtered soil extract) were more estrogenic than the mixtures containing greater amounts of TCDD-like compounds. Some antagonistic effects were observed in P450 enzyme activity as well as uterotropic responses between the mixtures containing TCDD-like compounds and non-TCDD-like compounds. These results indicate that both TCDD-like and non-TCDD-like effects of PCBs should be considered in assessing the potential hazards of environmental PCB mixtures.U of I OnlyETDs are only available to UIUC Users without author permissio
Recently, investigators have reported bioaccumulation of polychlorinated biphenyls (PCBs) in inse... more Recently, investigators have reported bioaccumulation of polychlorinated biphenyls (PCBs) in insects collected at hazardous waste sites. Little is known about differences in bioaccumulation of particular PCB congeners in insects. The authors report on the toxicokinetics of a non-coplanar ortho substituted congener, 2,2&#39;,4,4&#39;-tetrachlorobiphenyl (PCB-47) and a coplanar non-ortho substituted PCB, 3,3&#39;,4,4&#39;-tetrachlorobiphenyl (PCB-77) in topically treated house crickets. Penetration and excretion were more rapid for PCB-47 than for PCB-77. PCB-47 demonstrated a high affinity for abdomen, gut, and gonads, whereas, PCB-77 had a greater affinity for the head and thorax. Sex differences were observed in excretion and distribution. Females had an increased excretion of PCBs and increased accumulation in gut and gonads compared to males. Differences in lipophilicity can explain differences in distribution between sexes and of compounds within sexes. However, to explain the observed difference in penetration, it is necessary to invoke explanations based on stearic factors associated with coplanarity of the molecules. Differences in excretion are likely related to sex differences in mixed-function oxidase activities. These toxicokinetic data suggest that the more toxic coplanar congener, PCB-77, is likely to be more persistent in crickets compared to PCB-47, despite its lower lipophilicity.
Fig. 3. Mean percentage cover (±SE) of algae and sessile animals on seawalls, breakwaters, and na... more Fig. 3. Mean percentage cover (±SE) of algae and sessile animals on seawalls, breakwaters, and natural rocky shores at the 2 ports sampled from autumn 2010 to summer 2011 (n = 10). In the same season, means with different letters indicate significant differences according to Student-Newman-Keuls test (p <0.05).
Fig. 1. Location of study sites. (A) Taiwan, (B) the northern coast of Taiwan, (C) Houcuo fishing... more Fig. 1. Location of study sites. (A) Taiwan, (B) the northern coast of Taiwan, (C) Houcuo fishing port, and (D) Linshanbi fishing port.
Fig. 2. Mean density (±SE) of mobile molluscs on seawalls, breakwaters, and natural rocky shores,... more Fig. 2. Mean density (±SE) of mobile molluscs on seawalls, breakwaters, and natural rocky shores, at Houcuo and Linshanbi fishing ports between autumn 2010 and summer 2011. In the same season, means with different letters indicate significant differences according to Student-Newman-Keuls test (p <0.05).
Fluctuating asymmetry (FA) is defined as small, random deviation from perfect bilateral symmetry ... more Fluctuating asymmetry (FA) is defined as small, random deviation from perfect bilateral symmetry of morphological trait and an increase of FA is proposed to be caused by genetic and environmental stress. In this study, measures of FA in the shore crab, Grapsus albolineatus, were used to investigate the impact of a municipal landfill on the surrounding coastal area of northern Taiwan based on a hypothesis that poor environmental conditions can increase degrees of FA. The majority of leg segments examined showed higher mean FA levels in crabs collected from Pa-Dor-Tze than those from either of the control sites. There were significant increases in FA levels in eleven of sixteen leg segments in crabs collected from Pa-Dor-Tze compared to those from Wai-Mon-San, and four of sixteen leg segments in crabs collected from Pa-Dor-Tze compared to those from Red-Ben. Furthermore, there were significant increases in eight of nine composite FA indexes in crabs collected from Pa-Dor-Tze compared ...
The interactions among climate change, air pollution, and human health are multiple and complex. ... more The interactions among climate change, air pollution, and human health are multiple and complex. Many epidemiological studies in Taiwan have consistently demonstrated the effects of short-term exposures to extreme weather events, particulate matter, and traffic-related air pollutants on a variety of health effects. However, these findings might not explain or predict overall seasonal mortality patterns to provide insights into the drivers of mortality acting on society levels for public health policy and practice. There are very limited studies on seasonality of weather, air pollution, and mortality in Taiwan. The objectives of this study are to evaluate if there are any changes in trends and seasonality of mortality in three major Taiwanese cities from 1991 to 2010 and examine its association with climatic condition and air pollution. Among these major Taiwanese cities, seasonal mortality patterns are similar in two subtropical cities, Taipei and Taichung, compared to another tropical city, Kaohsiung. Taipei had significantly increased trends in most monthly temperature variables and the number of hot days examined during 1991–2010 compared to the other two cities. Winter/summer ratios of mortality only showed a decreased trend in Taipei, but not in Taichung or Kaohsiung. Mean monthly ambient temperature was also found as the most optimal temperature variable for predicting all-cause monthly mortality at all three cities in this study. Seasonal mortality patterns in three cities were with higher levels of deaths from December to March. Trends in air quality are showing mixed patterns over the past two decades. SO2, CO, and NOx concentrations have decreased significantly and steadily, while O3 has significantly increased in recent years. In three major Taiwanese cities, O3 and PM10 are major air pollutants of current concerns. The results of this study showed that monthly mean O3, PM10, and NOx levels and monthly mortality were not closely related, but temperature-related variables were positively associated with monthly mortality among three major Taiwanese cities. Moreover, changes in other socioeconomic and demographic factors may also play a key role in determining seasonality mortality and morbidity and need to be considered in future studies.
Effects of climate change on human health become increasingly a growing concern. Especially, the ... more Effects of climate change on human health become increasingly a growing concern. Especially, the worldwide risk of vector-borne diseases, such as dengue fever, could be strongly influenced by meteorological conditions. Taiwan is unique in terms of its geographical location and abundant ecological environments. It makes Taiwan an unusual epidemic region for dengue disease. This chapter focuses on risk factors related to climate change and geographical characteristics which have been shown to affect dengue transmission in Taiwan. Empirical studies all concluded that relationship between temperature and dengue incidence is highly correlated. Some of studies also concluded that temperature increase has more dramatic influence to dengue incidences in southern Taiwan. However, the effects of other meteorological factors, including precipitation and humidity, on dengue incidence are rather inconsistent. Extreme weather events, such as heavy rainfall, would be possible to damage the habitat...
Polychlorinated biphenyls (PCBs) are considered potential endocrine disruptors due to their abili... more Polychlorinated biphenyls (PCBs) are considered potential endocrine disruptors due to their ability to act as estrogens, antiestrogens and goitrogens. The aim of this study is to ascertain whether acute postnatal treatment with 3,3 0 ,4,4 0 -tetrachlorobiphenyl (CB 77) affects sperm function and hormone levels in adult rats. Male Sprague–Dawley rats received CB 77 by ip injection of 2 or 20 mg/kg at day 21 and sacrificed at day 112. At day 112, right and left testis weights were significantly increased, whereas sperm count, motility, total motile sperm count, curvilinear velocity, average path velocity, straight-line velocity, and beat-cross frequency for motile sperm were significantly decreased in rats treated with 20 mg/kg CB 77. Sperm–oocyte penetration rate was significantly reduced in rats treated with either 2 or 20 mg/kg CB 77. There was high sperm acrosome reaction rate (ARR) in the 20 mg/kg CB 77-treated rats. There was a significant increase in thyroid-stimulating hormone...
Both social and natural environments have profound effects on human health. This paper attempts t... more Both social and natural environments have profound effects on human health. This paper attempts to present an overview of recent environmental health status and related studies conducting in Taiwan. First, temporal trends of environmental health status in Taiwan are described. Then, regional variations of environmental health in Taiwan are discussed. Finally, different studies on relationships between human health and environment in Taiwan are introduced and examined. More work still needs to be done in order to give a complete perspective on geographical dimensions of disease occurrence and health care to improve our health policy in different parts of Taiwan.
The interactions among climate change, air pollution, and human health are multiple and complex. ... more The interactions among climate change, air pollution, and human health are multiple and complex. Many epidemiological studies in Taiwan have consistently demonstrated the effects of short-term exposures to extreme weather events, particulate matter, and traffic-related air pollutants on a variety of health effects. However, these findings might not explain or predict overall seasonal mortality patterns to provide insights into the drivers of mortality acting on society levels for public health policy and practice. There are very limited studies on seasonality of weather, air pollution, and mortality in Taiwan. The objectives of this study are to evaluate if there are any changes in trends and seasonality of mortality in three major Taiwanese cities from 1991 to 2010 and examine its association with climatic condition and air pollution. Among these major Taiwanese cities, seasonal mortality patterns are similar in two subtropical cities, Taipei and Taichung, compared to another tropical city, Kaohsiung. Taipei had significantly increased trends in most monthly temperature variables and the number of hot days examined during 1991-2010 compared to the other two cities. Winter/summer ratios of mortality only showed a decreased trend in Taipei, but not in Taichung or Kaohsiung. Mean monthly ambient temperature was also found as the most optimal temperature variable for predicting all-cause monthly mortality at all three cities in this study. Seasonal mortality patterns in three cities were with higher levels of deaths from December to March. Trends in air quality are showing mixed patterns over the past two decades. SO 2 , CO, and NO x concentrations have decreased significantly and steadily, while O 3 has significantly increased in recent years. In three major Taiwanese cities, O 3 and PM 10 are major air pollutants of current concerns. The results of this study showed that monthly mean O 3 , PM 10 , and NO x levels and monthly mortality were not closely related, but temperature-related variables were positively associated with monthly mortality among three major Taiwanese cities. Moreover, changes in other socioeconomic and demographic factors may also play a key role in determining seasonality mortality and morbidity and need to be considered in future studies.
Effects of climate change on human health become increasingly a growing concern. Especially, the ... more Effects of climate change on human health become increasingly a growing concern. Especially, the worldwide risk of vector-borne diseases, such as dengue fever, could be strongly infl uenced by meteorological conditions. Taiwan is unique in terms of its geographical location and abundant ecological environments. It makes Taiwan an unusual epidemic region for dengue disease. This chapter focuses on risk factors related to climate change and geographical characteristics which have been shown to affect dengue transmission in Taiwan. Empirical studies all concluded that relationship between temperature and dengue incidence is highly correlated. Some of studies also concluded that temperature increase has more dramatic infl uence to dengue incidences in southern Taiwan. However, the effects of other meteorological factors, including precipitation and humidity, on dengue incidence are rather inconsistent. Extreme weather events, such as heavy rainfall, would be possible to damage the habitats of Aedes mosquitoes and also benefi cial to construct them with lag time of several weeks. The role of extreme weather events in dengue transmission needs to be further investigated. Further studies should also put more focus on the extent of infl uence of meteorological conditions on human activities and what activity changes may increase or decrease the risk of dengue transmission.
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