Environmental Health and Preventive Medicine最新文献

Background: Dioxin is an environmental pollutant as well as an endocrine disruptor in humans. Our longitudinal study wants to clarify the relationship between dioxin exposure and endocrine disorders in children living in the Vietnamese dioxin hotspot.

Method: Seventeen congeners of polychlorinated dibenzo-p-dioxins/polychlorinated dibenzo-furans (PCDDs/PCDFs) in maternal breast milk and seven serum steroid hormones in children of 43 and 46 mothers and their 9-year-old children from the non-exposure and the hotspot areas were measured, respectively. The steroid metabolic enzyme ratios were calculated based on the hormone level ratio.

Results: Most dioxin/furan congeners and toxic equivalents (TEQs) levels were significantly higher in the hotspot than in the non-exposure area, except for 2,4,7,8-TeCDF. The height and weight of girls from the hotspot area were substantially lower and inversely correlated with dioxin congener levels/total TEQs level dioxin. The dihydrotestosterone (DHT) levels in the hotspot were markedly lower than those in non-exposed in both genders. The cortisol concentrations were significantly higher in the hotspot than those from the non-exposure area only in the girls. The DHT/testosterone ratios that exhibited the 5α- or 5β-reductase activity declined by 50% in the hotspot area for both genders. The DHT levels showed strong inverse correlations with almost the PCDDs/PCDFs congeners and total TEQs dioxin in breast milk.

Conclusions: This finding suggests that dioxin exposure in maternal breast milk might impact children's endocrine system until 9 years old, especially on the DHT biosynthesis.

Background: Home hot-tub bathing substantially increases drowning mortality rates among older adults in Japan. Previous laboratory studies on hemodynamic responses during hot-tub bathing have been inconsistent depending on the thermal conditions. Furthermore, real-world hemodynamic changes that occur during bathing remain poorly understood. This study investigated the association between individual thermal states and hemodynamic parameters during hot-tub bathing among community-dwelling older adults.

Methods: In this cross-sectional study conducted between January 2016 and April 2019, which involved 1,479 older adults (median [range] age, 68 [40-90] years), skin temperature on the abdominal surface was measured every minute. Ambulatory blood pressure and pulse rate were recorded at 15-min intervals for 24 h. Participants underwent simultaneous living room temperature measurements in their homes, and the time and methods of bathing were recorded. Associations between skin temperature and hemodynamic parameters during bathing and between the pre-bath living room temperature and in-bath maximum proximal skin temperature were evaluated using mixed-effects and linear regression models, respectively.

Results: A 1 °C increase in skin temperature was significantly associated with a 2.41 mmHg (95% confidence interval [CI]: 2.03-2.79) increase in systolic blood pressure and a 2.99 bpm (95% CI: 2.66-3.32) increase in pulse rate, after adjusting for potential confounders, including age, sex, body mass index, antihypertensive medication use, dyslipidemia, diabetes, and living room and outdoor temperatures. Significant interactions were not observed between sex and skin temperature in relation to systolic blood pressure and pulse rate (P = 0.088 and 0.490, respectively). One standard deviation lower living room temperature before bathing was significantly associated with a 0.41 °C (95% CI: 0.35-0.47) higher maximum skin temperature during bathing.

Conclusions: Our findings suggest that pre-bath cold exposure may increase the skin temperature during hot-tub bathing, possibly resulting in excessive hemodynamic changes. This provides a framework for future interventions that utilize pre-bath thermal conditions and bathing environments to prevent bath-related deaths.

Background: The projection indicates that compound drought and hot events (CDHEs) will intensify, posing risks to cardiovascular health by potentially increasing stroke incidents. However, epidemiological evidence on this topic remains scarce. This study investigates the association between exposure to CDHEs and the risk of daily stroke admissions, specifically examining the effects on various stroke categories such as Subarachnoid Hemorrhage (SAH), Intracerebral Hemorrhage (ICH), Ischemic Stroke (IS), Transient Ischemic Attack (TIA), and other types of stroke.

Methods: Data on daily stroke admissions from 2010 to 2015 were obtained from the Urban Employee Basic Medical Insurance (UEBMI) and Urban Resident Basic Medical Insurance (URBMI) claims databases in Guangzhou, China. Hot events were identified as days when the daily mean temperature exceeded the 75th percentile during the warm season (May to October) over the study period. The Standardized Precipitation Evapotranspiration Index (SPEI) was utilized to identify drought conditions, with thresholds set at -1 and -1.5 for low-severity and high-severity drought events, respectively. Through a generalized additive model (GAM), we analyzed the cumulative effects of CDHE exposure on daily stroke admissions and calculated the Attributable Fraction (AF) related to CDHEs.

Results: The analysis included 179,963 stroke admission records. We observed a significant increase in stroke admission risks due to exposure to hot events coupled with high-severity drought conditions (RR = 1.18, 95%CI: 1.01-1.38), with IS being the most affected category (RR = 1.20, 95%CI: 1.03-1.40). The AF of total stroke admission attributed to hot events in conjunction with high-severity drought conditions was 24.40% (95%CI: 1.86%-50.20%).

Conclusion: The combination of hot events with high-severity drought conditions is likely linked to an increased risk of stroke and IS admissions, which providing new insights into the impact of temperature and climate-related hazards on cardiovascular health.

Background: Coronavirus disease 2019 (COVID-19), first reported in December 2019, spread worldwide in a short period, resulting in numerous cases and associated deaths; however, the toll was relatively low in East Asia. A genetic polymorphism unique to East Asians, Aldehyde dehydrogenase 2 rs671, has been reported to confer protection against infections.

Method: We retrospectively investigated the association between the surrogate marker of the rs671 variant, the skin flushing phenomenon after alcohol consumption, and the timing of COVID-19 incidence using a web-based survey tool to test any protective effects of rs671 against COVID-19.

Results: A total of 807 valid responses were received from 362 non-flushers and 445 flushers. During the 42 months, from 12/1/2019 to 5/31/2023, 40.6% of non-flushers and 35.7% of flushers experienced COVID-19. Flushers tended to have a later onset (Spearman's partial rank correlation test, p = 0.057, adjusted for sex and age). Similarly, 2.5% of non-flushers and 0.5% of flushers were hospitalized because of COVID-19. Survival analysis estimated lower risks of COVID-19 and associated hospitalization among flushers (p = 0.03 and <0.01, respectively; generalized Wilcoxon test). With the Cox proportional hazards model covering 21 months till 8/31/2021, when approximately half of the Japanese population had received two doses of COVID-19 vaccine, the hazard ratio (95% confidence interval) of COVID-19 incidence was estimated to be 0.21 (0.10-0.46) for flusher versus non-flusher, with adjustment for sex, age, steroid use, and area of residence.

Conclusions: Our study suggests an association between the flushing phenomenon after drinking and a decreased risk of COVID-19 morbidity and hospitalization, suggesting that the rs671 variant is a protective factor. This study provides valuable information for infection control and helps understand the unique constitutional diversity of East Asians.

Background: Non-optimum temperatures are associated with increased risk of respiratory diseases, but the effects of apparent temperature (AT) on respiratory diseases remain to be investigated.

Methods: Using daily data from 2016 to 2020 in Ganzhou, a large city in southern China, we analyzed the impact of AT on outpatient and inpatient visits for respiratory diseases. We considered total respiratory diseases and five subtypes (influenza and pneumonia, upper respiratory tract infection (URTI), lower respiratory tract infection (LRTI), asthma and chronic obstructive pulmonary disease [COPD]). Our analysis employed a distributed lag nonlinear model (DLNM) combined with a generalized additive model (GAM).

Results: We recorded 94,952 outpatients and 72,410 inpatients for respiratory diseases. We found AT significantly non-linearly associated with daily outpatient and inpatient visits for total respiratory diseases, influenza and pneumonia, and URTI, primarily during comfortable AT levels, while it was exclusively related with daily inpatient visits for LRTI and COPD. Moderate heat (32.1 °C, the 75.0th centile) was observed with a significant effect on both daily outpatient and inpatient visits for total respiratory diseases at a relative risk of 1.561 (1.161, 2.098) and 1.276 (1.027, 1.585), respectively (both P < 0.05), while the results of inpatients became insignificant with the adjustment for CO and O₃. The attributable fractions in outpatients and inpatients were as follows: total respiratory diseases (24.43% and 18.69%), influenza and pneumonia (31.54% and 17.33%), URTI (23.03% and 32.91%), LRTI (37.49% and 30.00%), asthma (9.83% and 3.39%), and COPD (30.67% and 10.65%). Stratified analyses showed that children ≤5 years old were more susceptible to moderate heat than older participants.

Conclusions: In conclusion, our results indicated moderate heat increase the risk of daily outpatient and inpatient visits for respiratory diseases, especially among children under the age of 5.

Background: Depression substantially impacts on quality of life, personal relationships, and self-care. Gastrointestinal disorders are the common comorbidity of depression and 24.3% of patients with depression have disordered bowel habits. Dietary intake of live microbes alters the host's microflora and is beneficial for the prevention and control of bowel health and depression. We aim to investigate the association of dietary intake of live microbes with bowel health and depression and to further examine weather bowel health or depression mediates the therapeutic effect of live microbes.

Methods: Participants' data were obtained from the National Health and Nutrition Examination Survey (NHANES) 2005-2010, which is designed to examine the health and nutritional status of the non-institutionalized US population by a complex, multi-stage, probability sampling design. The foods were grouped into categories on the basis of estimated microbial levels: low (<10⁴ CFUs/g), medium (Med; 10⁴-10⁷ CFU/g), and high (Hi; >10⁷ CFU/g). Participants were further classified into three groups (G1: participants without MedHi foods intakes; G2: those with MedHi foods intakes greater than zero but less than the median; and G3: those with MedHi foods intakes greater than the median).

Results: A total of 10,785 US adults were selected. The median of MedHi foods intake was 66.1 g/day. Participants in the G2 (OR = 0.739, 95% CI: 0.581-0.941) and G3 (OR = 0.716, 95% CI: 0.585-0.877) groups had significant association with lower risks of depression, and participants in the G3 group had significant association with lower risks of hard stools (OR = 0.885, 95% CI: 0.692-0.989) and loose stools (OR = 0.769, 95% CI: 0.585-0.954). Interestingly, further mediation analyses showed that the association of dietary live microbe intake with depression is mediated by the stool types, and the association of dietary live microbe intake with stool types is mediated by the depression (all P < 0.05).

Conclusions: A high dietary intake of live microbes, especially a minimum of 66.1 g of MedHi foods per day, is associated with a lower risk of depression, hard stools, and loose stools consistency. Depression and bowel health mutually act as mediators in this association, indicating dietary intake of live microbes may simultaneously affect bowel health and depression.

Background: Cleft lip and/or palate (CL/P) is one of the most frequent craniofacial disorder which could associate with a wide range of craniofacial complication. In order to perform comprehensive care of CL/P patients, it is crucial to elucidate the link of CL/P and general clinical conditions. This study aims to elucidate the relationships between medical history of different CL/P types and infectious diseases to serve as a reference for the comprehensive care of patients with CL/P.

Methods: We investigated the association between a history different types of CL/P and the risk of infectious diseases among 1-year old children in the Japan Environment and Children's Study (JECS). Among the 104,065 registered fetal records, 92,590 eligible participants were included in the analysis.

Results: The multivariable-adjusted risk ratios (95% confidence intervals) for otitis media were increased in cleft lip and palate (CLP) and cleft palate only (CPO) groups by 3.81 (2.73-5.31) and 2.27 (1.22-4.22), respectively. The prevalence of Upper respiratory inflammation (URTI) was not associated with CLP, cleft lip only, or CPO. However, analysis in all groups showed a higher risk of URTI compared with the control group (1.31 [1.04-1.66]).

Conclusions: CL/P care requires additional attention to prevent airway infectious diseases such as URTI before 1 year of age. Further research is warranted to elucidate the relationship between CL/P and general medical conditions.

Background: Plastic additives have adverse effects on human health. Children frequently use toys that contain various substances found in paints, plasticizers, and other materials, which heighten the risk of specific chemical exposure. Infants are particularly prone to chemical exposure through the "mouthing" behavior because of the possibility of placing toys in their mouths. Thus, this vulnerability should be considered during risk assessments of chemical exposure.

Methods: This study performed a comprehensive analysis of the chemical components in various 84 plastic toys including "designated toys" (toys that may be harmful to infant health if in contact with their mouths: Article 78 of the Enforcement Regulations of the Food Sanitation Law by the Minister of Health, Labor and Welfare) such as dolls, balls, blocks, bathing toys, toy vehicles, pacifiers, and household items, purchased in the Japanese market by nontargeted and targeted analysis.

Results: Plasticizers, flame retardants, and fragrances were the main compounds in almost all the toy products. The results showed that plastic products made in China tended to contain high levels of phthalate esters. In particular, hazardous plasticizers, such as diisodecyl, di-n-octyl, and diisononyl phthalates were detected above the regulatory limit (0.1%) in used products manufactured before regulations were passed in Japan. Furthermore, we detected alternative plasticizers, such as acetyl tributyl citrate (ATBC; 52%), diisononyl adipate (DINA; 50%), and di(2-ethylhexyl) terephthalate (DEHT; 40%). ATBC was detected at high concentrations in numerous toy products. Thus, infants with free access to indoor plastic toys might be exposed to these chemicals.

Conclusions: This study observed that the chemical profiles of toy products were dependent on the year of manufacture. Furthermore, the detection of currently regulated plasticizers in secondhand products manufactured before regulations were enforced, along with the increasing trend of using alternative substances to regulated phthalate esters in products, suggests the potential exposure of infants to these plasticizers through the use of toys. Therefore, regular fact-finding surveys should continue to be conducted for the risk assessment and safety management of domestic toy products.

Background: Global warming and increasing extreme weather have become a severe problem in recent years, posing a significant threat to human health worldwide. Research exploring the link between injury as one of the leading causes of death globally and ambient temperature was lacking. Based on the hourly injury emergency ambulance dispatch (IEAD) records from 2019-2021 in the main urban area of Chongqing, this study explored the role of temperature extremes on the pathogenesis of injury by different mechanisms and identified sensitive populations for different mechanisms of injury.

Methods: In this study, we collected hourly injury emergency ambulance dispatch (IEAD) records from Chongqing Emergency Dispatch Center in the main urban area of Chongqing from 2019 to 2021, and used a distributed lagged nonlinear model (DLNM) with quasi-Poisson distribution to evaluate the association between ambient temperature and IEADs. And the stratified analysis was performed by gender, age and different injury mechanisms to identify susceptible groups. Finally, the attributable burden of ambient extreme temperatures was also investigated.

Results: The risk for total IEADs increased significantly at high temperature (32 °C) compared with optimal temperature (9 °C) (CRR: 1.210; 95%CI[1.127,1.300]). The risks of traffic accident injury (CRR: 1.346; 95%CI[1.167,1.552]), beating injury (CRR: 1.508; 95%CI[1.165,1.952]), fall-height injury (CRR: 1.871; 95%CI[1.196-2.926]) and injury of sharp penetration (CRR: 2.112; 95%CI[1.388-3.213]) were significantly increased. At low temperature (7 °C), the risk of fall injury (CRR: 1.220; 95% CI [1.063,1.400]) increased significantly. Lag for 24 hours at extreme low temperature (5 °C), the risk of 18-45 years (RR: 1.016; 95%CI[1.009,1.024]) and over 60 years of age (RR: 1.019; 95%CI[1.011,1.025]) increased significantly. The effect of 0 h delay in extreme high temperature (36 °C) on males aged 18-45 years (RR: 1.115; 95%CI[1.071,1.162]) and 46-59 years (RR: 1.069; 95%CI[1.023,1.115]) had significant impact on injury risk.

Conclusions: This study showed that ambient temperature was significantly related to the risk of injury, and different mechanisms of injury were affected differently by extreme temperature. The increasing risk of traffic accident injury, beating injury, fall-height injury and sharp penetrating injury was associated with extreme heat, while fall injury was associated with extreme cold. The risk of injury in high temperature environment was mainly concentrated in males and young adults. The results of this study can help to identify the sensitive population with different injury mechanisms in extreme temperature environment, and provide reference for public health emergency departments to respond to relevant strategies in extreme temperature environment to minimize the potential risk to the public.