Do expressive writing interventions have positive effects on Koreans?: a meta-analysis.

Introduction: Expressive Writing (EW) is an intervention that focuses on individuals' writing down their thoughts and feelings about trauma or stressful events. Meta-analyses on EW studies have confirmed that EW has a positive effect. However, the heterogeneity of studies is high, so many studies have investigated boundary conditions and moderators. One of these moderators is the cultural difference in emotional suppression. Since EW focuses on the expression of suppressed thoughts and emotions, its effect might be slightly different for people in Asian cultures who show a high tendency to suppress their emotions. This study attempted to confirm the effect size of the EW interventions in Korea and examine whether these studies have different effect size from those based on Western cultures. Method: A total of 29 studies published in Korea until 2021 were analyzed. The effect size was calculated using the "dmetar," "meta," and "metafor" packages of the statistical program R 4.0.4. Results: The results were as follows. First, the effect size of EW intervention was 0.16, and we found that studies in the Korean context showed no significant difference from studies based on western meta-analysis. Second, the moderating variables that influenced the EW intervention were the writing type, the number of sessions, the time per session, and the measurement time. Discussion: The results of this study suggest that EW interventions benefit Koreans. And it is at least harmless and has a positive effect considering the efficiency and conciseness of interventions. Furthermore, the finding shows that EW interventions can be helpful even in the general population without apparent psychological problems. By considering moderators, we could structure more effective form of EW interventions for Koreans.

Serum metabolomic profile of hair dye use.

The International Agency for Research on Cancer reported that some chemicals in hair dyes are probably carcinogenic to those exposed to them occupationally. Biological mechanisms through which hair dye use may be related to human metabolism and cancer risk are not well-established. We conducted the first serum metabolomic examination comparing hair dye users and nonusers in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study. Metabolite assays were conducted using ultrahigh performance liquid chromatography-tandem mass spectrometry. The association between metabolite levels and hair dye use was estimated using linear regression, adjusting for age, body mass index, smoking, and multiple comparisons. Among the 1,401 detected metabolites, 11 compounds differed significantly between the two groups, including four amino acids and three xenobiotics. Redox-related glutathione metabolism was heavily represented, with L-cysteinylglycine disulfide showing the strongest association with hair dye (effect size (ß) = - 0.263; FDR adjusted p-value = 0.0311), along with cysteineglutathione disulfide (ß = - 0.685; FDR adjusted p-value = 0.0312). 5alpha-Androstan-3alpha,17beta-diol disulfate was reduced in hair dye users (ß = - 0.492; FDR adjusted p-value = 0.077). Several compounds related to antioxidation/ROS and other pathways differed significantly between hair dye users and nonusers, including metabolites previously associated with prostate cancer. Our findings suggest possible biological mechanisms through which the use of hair dye could be associated with human metabolism and cancer risk.

Metabolomic analysis of serum alpha-tocopherol among men in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study.

BACKGROUND/OBJECTIVES: The role of vitamin E in chronic disease risk remains incompletely understood, particularly in an un-supplemented state, and evidence is sparse regarding the biological actions and pathways involved in its influence on health outcomes. Identifying vitamin-E-associated metabolites through agnostic metabolomics analyses can contribute to elucidating the specific associations and disease etiology. This study aims to investigate the association between circulating metabolites and serum α-tocopherol concentration in an un-supplemented state. SUBJECTS/METHODS: Metabolomic analysis of 4,294 male participants was conducted based on pre-supplementation fasting serum in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study. The associations between 1,791 known metabolites measured by ultra-high-performance LC-MS/GC-MS and HPLC-determined α-tocopherol concentration were estimated using multivariable linear regression. Differences in metabolite levels per unit difference in α-tocopherol concentration were calculated as standardized ß-coefficients and standard errors. RESULTS: A total of 252 metabolites were associated with serum α-tocopherol at the Bonferroni-corrected p value (p < 2.79 × 10-5). Most of these metabolites were of lipid and amino acid origin, with the respective subclasses of dicarboxylic fatty acids, and valine, leucine, and isoleucine metabolism, being highly represented. Among lipids, the strongest signals were observed for linoleoyl-arachidonoyl-glycerol (18:2/20:4)[2](ß = 0.149; p = 8.65 × 10-146) and sphingomyelin (D18:2/18:1) (ß = 0.035; p = 1.36 × 10-30). For amino acids, the strongest signals were aminoadipic acid (ß = 0.021; p = 5.01 × 10-13) and l-leucine (ß = 0.007; p = 1.05 × 10-12). CONCLUSIONS: The large number of metabolites, particularly lipid and amino acid compounds associated with serum α-tocopherol provide leads regarding potential mechanisms through which vitamin E influences human health, including its role in cardiovascular disease and cancer.

A 28-year prospective analysis of serum vitamin E, vitamin E-related genetic variation and risk of prostate cancer.

OBJECTIVE: Investigate the relationship between serum α-tocopherol concentration and long-term risk of prostate cancer, and evaluate the interaction with vitamin E-related genetic variants and their polygenic risk score (PRS). METHODS: We conducted a biochemical analysis of 29,102 male Finnish smokers in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study. Serum α-tocopherol was measured at baseline using high-performance liquid chromatography, and 2724 prostate cancer cases were identified during 28 years of follow-up. Cox proportional hazards models examined whether serum α-tocopherol concentrations were associated with prostate cancer risk. Among 8383 participants, three SNPs related to vitamin E status (rs964184, rs2108622, and rs11057830) were examined to determine whether they modified the relationship between serum α-tocopherol concentrations and prostate cancer risk, both individually and as a PRS using logistic regression models. RESULTS: No association was observed between serum α-tocopherol and prostate cancer risk (fifth quintile (Q5) vs. Q1 hazard ratio (HR) = 0.87, 95% confidence interval (95% CI) 0.75, 1.02; P-trend = 0.57). Though no interactions were seen by population characteristics, high α-tocopherol concentration was associated with reduced prostate cancer risk among the trial α-tocopherol supplementation group (Q5 quintile vs. Q1 HR = 0.79, 95% CI 0.64, 0.99). Finally, no associated interaction between the three SNPs or their PRS and prostate cancer risk was observed. CONCLUSION: Although there was a weak inverse association between α-tocopherol concentration and prostate cancer risk over nearly three decades, our findings suggest that men receiving the trial α-tocopherol supplementation who had higher baseline serum α-tocopherol concentration experienced reduced prostate cancer risk. Vitamin E-related genotypes did not modify the serum α-tocopherol-prostate cancer risk association.

Multivitamin Use and Overall and Site-Specific Cancer Risks in the National Institutes of Health-AARP Diet and Health Study.

BACKGROUND: Multivitamins are among the most commonly used supplements in the United States, but their effectiveness in preventing cancer remains unclear. OBJECTIVES: We prospectively examined the association between multivitamin use and risks of overall and site-specific cancer in a large, well-characterized cohort to ascertain potential preventive or harmful relationships. METHODS: We examined 489,640 participants ages 50-71 in the NIH-American Association of Retired Persons (AARP) Diet and Health Study who were enrolled from 1995 to 1998. We linked to 11 state cancer registries in order to identify incident cancers. Multivitamin use was assessed by a baseline questionnaire. Cox proportional hazards regression models of multivitamin use were used to estimate HRs and 95% CIs for cancer risks in men and women, adjusted for potential confounders, including age, BMI, smoking, physical activity, the Healthy Eating Index 2015 score, and use of single-vitamin/-mineral supplements. RESULTS: A slightly higher overall cancer risk was observed in men (but not women) who consumed 1 or more multivitamins daily compared to nonusers [HRs, 1.02 (95% CI: 1.01-1.04) and 1.03 (95% CI: 1.00-1.07), respectively; P-trend = 0.002]. The latter reflected higher risks for prostate cancer (HR, 1.04; 95% CI: 0.98-1.10; P-trend = 0.005), lung cancer (HR, 1.07; 95% CI: 0.96-1.20; P-trend = 0.003), and leukemia (HR, 1.26; 95% CI: 1.02-1.57; P-trend = 0.003). Taking more than 1 multivitamin daily was also strongly positively associated with the risk of oropharyngeal cancer in women (HR, 1.53, 95% CI: 1.04-2.24; P-trend < 0.0001). By contrast, daily multivitamin use was inversely associated with the colon cancer risk in both sexes (HR, 0.82; 95% CI: 0.73-0.93; P-trend = 0.0003). CONCLUSIONS: We found little evidence to support a cancer-preventive role for multivitamin use, with the exception of colon cancer, in both sexes in the NIH-AARP Diet and Health Study. In addition, slightly higher risks of overall, prostate, and lung cancer, as well as leukemia, were observed for greater multivitamin use in men, with a higher oropharyngeal cancer risk in women.

Hair dye use and prostate cancer risk: A prospective analysis in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study cohort.

BACKGROUND: According to the International Agency for Research on Cancer, some hair dye chemicals are considered mutagenic and carcinogenic in humans. One hospital-based study reported a positive association between hair dye use and prostate cancer risk, but no prospective analyses have been conducted. METHODS: This study investigated the association between hair dye use and prostate cancer risk in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study cohort, a large, well-characterized cohort of 29,133 male Finnish smokers. Participants completed questionnaires regarding lifestyle, medical, and risk factor information, including the use of hair dye, which was available for 98.8% of the cohort (28,795 men). Prostate cancer cases were identified through linkage with the Finnish Cancer Registry and the Finnish Mortality Register. Hazard ratios (HRs) and confidence intervals (CIs) were estimated via multivariable Cox proportional hazards regression. RESULTS: During a 28-year period of observation, 2703 incident prostate cancer cases were diagnosed. As reported at the baseline, 75 men used hair dye, and 13 of these men were subsequently diagnosed with prostate cancer. After adjustments for potential confounders, men who used hair dyes experienced substantially higher prostate cancer risk than men who did not (HR, 1.77; 95% CI, 1.03-3.05). CONCLUSIONS: This first prospective investigation of hair dye use and prostate cancer suggests that personal hair dye use may be related to increased risk. The findings warrant re-examination in other prospective cohorts along with studies evaluating specific hair dyes and possible underlying biological mechanisms.

Urinary bisphenol A, phthalate metabolites, and obesity: do gender and menopausal status matter?

Previous studies of urinary bisphenol A (BPA), phthalate metabolites, and obesity risk have shown inconsistent results. Menopausal status is one of the main factors that affect hormone secretion change in women. In this study, we examined whether urinary BPA and phthalate metabolite levels are associated with obesity and whether the associations differ by sex and menopausal status in a sample of Korean adult populations. We recruited participants at three branches (Yeouido, Gangnam, and Gwanghwamun) of the Korea Medical Institute, a nationwide health check-up center, from 2015 to 2016. Urinary BPA level was measured by high-performance liquid chromatography-tandem mass spectrometry (Agilent 6490 Triple Quad LC-MS/MS; Agilent Technologies, CA, USA). Urinary six phthalate metabolites were analyzed with ultra-high-performance liquid chromatography-tandem mass spectrometry (TSQ Quantum Access Mass; Thermo Fisher Scientific, MA, USA). Participants with body mass index ≥ 25 kg/m2 were defined as general obesity group. Men with waist circumference (WC) ≥ 90 cm and women with WC ≥ 85 cm were defined as abdominal obesity group. Age, sex, alcohol intake, smoking, and exercise were considered in multivariate logistic regression models. Among the total of 702 participants, 211 participants were classified into the general obesity group, and 131 participants were classified into the abdominal obesity group. Urinary phthalate metabolite levels were not associated with general and abdominal obesity in men and women. However, in women, urinary BPA concentration was positively associated with abdominal obesity (OR = 1.50, 95% CI 1.00-2.26). Also, the association was stronger in postmenopausal women (OR = 2.23, 1.01-4.92), while it was weak in premenopausal women (OR = 1.31, 0.78-2.20). In this study, urinary BPA concentration was associated with abdominal obesity in women, especially postmenopausal women. Future studies should consider sex and menopausal status when investigating associations between urinary BPA, phthalate metabolites levels, and obesity.

Effects of Combined Upper Limb Robotic Therapy in Patients With Tetraplegic Spinal Cord Injury.

OBJECTIVE: To confirm the effects of combined upper limb robotic therapy (RT) as compared to conventional occupational therapy (OT) in tetraplegic spinal cord injury (SCI) patients and to suggest the optimized treatment guidelines of combined upper limb RT. METHODS: After subject recruitment and screening for eligibility, the baseline evaluation for outcome measures were performed. We evaluated the Graded and Redefined Assessment of Strength, Sensibility, and Prehension (GRASSP), the American Spinal Injury Association upper extremity motor score, grip and pinch strength, and the Spinal Cord Independence Measurement III (SCIM-III). In this study, the pre-tested participants were divided randomly into the RT and OT group. The utilized interventions included combined upper limb RT using ArmeoPower and Amadeo (RT group), or conventional OT (OT group) in addition to daily inpatient rehabilitation program. The participants underwent 40 minutes×3 sessions×5 weeks of interventions. RESULTS: A total of 30 tetraplegic SCI patients completed entire study program. After 5 weeks of intervention, both groups demonstrated increases in GRASSP-strength and SCIM-III. The manual muscle test scores of elbow flexion, elbow extension, 2-5th metacarpophalangeal extension, and SCIM-III subscores of bathing-upper, dressing-upper, and grooming as well as the GRASSP-qualitative prehension score were noted to have been significantly increased in the RT group as evaluated. The OT group showed improvements in the GRASSP-quantitative prehension score and some items in grip and pinch strength. There was no significant difference between the two groups in almost all measurements except for the SCIM-III bathing-upper subscore. CONCLUSION: Combined upper limb RT demonstrated beneficial effects on the upper limb motor function in patients with tetraplegic SCI, which were comparable with conventional OT.

Correction: Clinical efficacy of upper limb robotic therapy in people with tetraplegia: a pilot randomized controlled trial.

In the original version of the article the authors incorrectly stated that: "One case study provided evidence of some improvements in motor performance and spasticity [19], while several other studies only provided evidence on the feasibility of UER as an assessment tool; however, the fact that the manufacturer funded these studies lessens their objectivity [15, 20-24]." This is not correct as the manufacturers did not fund the studies. The correct phrase therefore should have read: "One case study provided evidence of some improvements in motor performance and spasticity [19], while several other studies provided evidence focusing more on the feasibility of UER rather than the clinical efficacy [15, 20-24]." The authors would like to apologise for this error.This has been corrected in both the PDF and HTML versions of the Article.

Clinical efficacy of upper limb robotic therapy in people with tetraplegia: a pilot randomized controlled trial.

STUDY DESIGN: A pilot randomized controlled trial. OBJECTIVES: To evaluate the clinical efficacy of upper limb robotic therapy in people with tetraplegia. SETTING: Inpatient rehabilitation hospital in Seoul, Korea. METHODS: Participants were randomly allocated to a robotic therapy (RT) or occupational therapy (OT) group. Both groups received usual care plus 30 min of additional therapy per day for 4 weeks. The additional therapy provided to the OT group was OT, and the additional therapy provided to RT group was RT using the Armeo Power. Primary outcomes were the Medical Research Council scale of each key muscle and Upper Extremity Motor Score (UEMS) for the trained arm. Secondary outcomes were the Spinal Cord Independence Measurement version III (SCIM-III) subscale and total score. Evaluations were performed at baseline and 4 weeks. RESULTS: A total of 34 individuals with tetraplegia were included; 17 in each group. At 4 weeks, the median (IQR) change in UEMS in the RT group was 1/25 (0 to 3) points compared with 0/25 (-1 to 1) points in the OT group (p = 0.03). The median (IQR) change in total SCIM-III score in the RT group was 7/100 (1.5 to 11) points compared with 0/100 (-8 to 4) points in the OT group (p < 0.01). CONCLUSIONS: There were small improvements in motor strength and SCIM-III scores in the RT group, but there were no statistically significant differences between the groups. Further studies are required for a better understanding of the effects of RT for people with tetraplegia.

Bisphenol A exposure and type 2 diabetes mellitus risk: a meta-analysis.

BACKGROUND: This meta-analytic study explored the relationship between the risk of type 2 diabetes mellitus (T2DM) and bisphenol A concentrations. METHODS: The Embase and Medline (PubMed) databases were searched, using relevant keywords, for studies published between 1980 and 2018. A total of 16 studies, twelve cross-sectional, two case-control and one prospective, were included in the meta-analysis. The odds ratio (OR) and its 95% confidence interval (CI) were determined across the sixteen studies. The OR and its 95% CI of diabetes associated with bisphenol A were estimated using both fixed-effects and random-effects models. RESULTS: A total of 41,320 subjects were included. Fourteen of the sixteen studies included in the analysis provided measurements of urine bisphenol A levels and two study provided serum bisphenol A levels. Bisphenol A concentrations in human bio-specimens showed positive associations with T2DM risk (OR 1.28, 95% CI 1.14, 1.44). A sensitivity analysis indicated that urine bisphenol A concentrations were positively associated with T2DM risk (OR 1.20, 95% CI 1.09, 1.31). CONCLUSIONS: This meta-analysis indicated that Bisphenol A exposure is positively associated with T2DM risk in humans.

Menopausal hormone therapy and the risk of breast cancer by histological type and race: a meta-analysis of randomized controlled trials and cohort studies.

PURPOSE: This meta-analysis investigated the association between the risk of breast cancer and hormone replacement therapy (HRT). Various stratified analyses were performed according to race (Asian/Westerner), HRT type [all hormone therapies, estrogen-only therapy (ET), or combined estrogen-progestin therapy (EPT)], histological breast cancer type (ductal/lobular/mixed ductal-lobular), and estrogen receptor status (ER-positive/ER-negative). METHODS: A literature search was performed using Pubmed, Embase, and KoreaMed. Twenty-five epidemiological studies including 23 cohort studies and two randomized controlled trials were included in this meta-analysis. RESULTS: Using a random-effects model, HRT use was found to be positively associated with the risk of breast cancer with a pooled hazard ratio (HR) of 1.33 [95% confidence interval (CI) 1.24, 1.44]. Compared with ET, EPT was more strongly associated with breast cancer risk. EPT was associated with both ductal and lobular breast cancer risks [for ductal breast cancer, HR = 1.51 (95% CI 1.28, 1.78); for lobular breast cancer, HR = 1.38 (95% CI 1.20, 1.60)]. According to ER status, all HRTs were associated with the risk of ER-positive breast cancer, but not with that of ER-negative breast cancer. CONCLUSIONS: Asian HRT users had a higher risk of breast cancer than western HRT users. Both ET and EPT were significantly associated with the risk of all breast cancer histological types and ER-positive breast cancer.

Serum persistent organic pollutants levels and stroke risk.

Knowledge of environmental risk factors for stroke and their role are limited. We performed a case-cohort study to evaluate the association between serum persistent organic pollutants (POPs) level and stroke risk. 526 subcohort members and 111 stroke incidence cases were identified from the Korean Cancer Prevention Study-II. Serum levels of POPs were measured using gas chromatography/high-resolution mass spectrometry. The hazard ratios (HRs) for stroke (ischemic, hemorrhagic, and all stroke types) were estimated using the weighted Cox regression model. Age, sex, body mass index, smoking status, physical activity, family history of cardiovascular disease, and hypertension were adjusted in the weighted Cox regression model. After adjusting for potential confounding factors, increased risk for stroke was observed among participants with serum concentration of p,p'-DDE in the highest tertile compared to those in the lowest tertile (HR = 4.10, 95% CI: 1.58, 10.59). A similar association was estimated for PCB118 (HR = 2.33, 95% CI: 1.04, 5.22), PCB156 (HR = 3.42, 95% CI: 1.42, 8.23), and PCB138 (HR = 3.80, 95% CI: 1.48, 9.76). For TEQ, stroke was three times as likely to occur among subjects with TEQ in the highest tertile compared to those in the lowest tertile (HR = 3.12, 95% CI: 1.27, 7.65). PCBs were positively associated with ischemic stroke, but not with hemorrhagic stroke. Elevated serum POPs levels were associated with an increased risk of stroke, especially ischemic stroke.

Association between serum persistent organic pollutants and DNA methylation in Korean adults.

BACKGROUND: Exposure to persistent organic pollutants (POPs) has been associated with epigenetic changes such as DNA methylation, which can influence human health. However, the association between POPs and DNA methylation by sex was not shown in previous studies. OBJECTIVES: We investigated the association between POPs and DNA methylation in men and women using a larger population. METHODS: A cross-sectional study was conducted using the data of 444 Koreans (253 men and 191 women). Measurements for sixteen different POPs, including six organochlorine pesticides (OCPs) and ten polychlorinated biphenyls (PCBs) were taken in serum. DNA methylation via Alu and LINE-1 in peripheral leukocytes was measured by pyrosequencing. To evaluate the association between POPs and DNA methylation, the Pearson's correlation and multiple linear regression analyses were performed. RESULTS: Except for PCB52 and PCB101, we found significant inverse associations between p,p'-DDE, cis-Heptachlor epoxide, and PCBs and Alu assay in men after adjusting for age, BMI, smoking status, and alcohol consumption (ß = -0.67 for p,p'-DDE; -0.28 for cis-Heptachlor epoxide; in the range from -0.43 to -1.60 for PCBs). In women, PCB153 and PCB180 showed statistically significant inverse association with Alu assay (ß = -0.22 for PCB153; -0.22 for PCB180). Except for PCB101, p,p'-DDE and PCBs were positively associated with LINE-1 assay in women (ß = 0.48 for p,p'-DDE; in the range from 0.40-0.89 for PCBs) while p,p'-DDE, PCB153, and PCB180 showed positive associations with LINE-1 assay in men (ß = 0.55 for p,p'-DDE; 0.65 for PCB153; 1.02 for PCB180). CONCLUSIONS: We found that several POPs were associated with global DNA hypomethylation in the Alu assay for men and global DNA hypermethylation in the LINE-1 assay for women.

Serum persistent organic pollutants (POPs) and prostate cancer risk: A case-cohort study.

It is still unclear whether persistent organic pollutants (POPs) exposure increases the prostate cancer incidence risk. This prospective cohort study evaluated the associations between serum POPs concentrations and prostate cancer risk. Within a case-cohort study, we identified 110 people diagnosed with prostate cancer and randomly selected 256 sub-cohort participants without prostate cancer. Serum concentrations of 32 polychlorinated biphenyl (PCB) congeners and 19 organochlorine pesticides (OCPs) were measured. The hazard ratios (HRs) and 95% confidence interval (95% CI) for determining the associations between POPs and risk of prostate cancer were estimated using the weighted Cox regression model. Compared to the lowest tertile, increased risks of prostate cancer incidence were observed in the upper tertile of following PCBs: the moderately chlorinated (HR: 4.19; 95% CI: 1.30-13.54), the highly chlorinated (HR: 4.14; 95% CI: 1.75-9.79), biologically persistent as CYP1A and CYP2B inducers (HR: 4.44; 95% CI: 1.33-14.83), the sum of non- dioxin-like (HR: 3.47; 95% CI: 1.21-9.98), and ∑PCBs (HR: 4.29; 95% CI: 1.52-12.08). In dose-response curves, ∑PCBs was associated with the increased risk of prostate cancer. Our findings suggested a possible role of POPs in the etiology of prostate cancer.

Association between serum concentrations of persistent organic pollutants and smoking in Koreans: A cross-sectional study.

BACKGROUND: Studies on the associations between persistent organic pollutants (POPs) and smoking according to gender and smoking amount (cigarettes/day) are limited, and the results regarding the relationship between POPs and smoking are not completely consistent across studies. OBJECTIVES: The smoking rate in Korea is one of the highest among the Organization for Economic Cooperation and Development (OECD) countries. We investigated the association between serum concentrations of POPs and cigarette smoking in Koreans by smoking status (never-smoker/ever-smoker) and smoking amount (cigarettes/day) according to gender. METHODS: Serum concentrations of 32 polychlorinated biphenyls (PCBs) and 19 organochlorine pesticides (OCPs) were measured in 401 participants (232 men and 169 women) who received health examinations during the Korean Cancer Prevention Study-II. We compared POP levels in ever-smokers and never-smokers and conducted multivariate logistic regression analyses to identify associations between POPs and smoking. RESULTS: Among women, the concentrations of PCB 156, PCB 167, and PCB 180 were significantly higher in ever-smokers than in never-smokers. After adjustments for age, body mass index, gamma-glutamyl transpeptidase, and alcohol intake, serum PCB 157 concentration was positively associated with male ever-smokers (OR 2.26; 95% CI, 1.01-5.04). In addition, trans-nonachlordane in OCPs as well as PCBs was significantly positively related with female ever-smokers (OR 3.21; 95% CI, 1.04-9.86). We found that subjects who smoked fewer than 15 cigarettes/day had a higher risk of having high POP concentrations than never-smokers. CONCLUSIONS: These results indicate that smoking may be associated with human serum POPs levels.

Impact of natural and calcined starfish (Asterina pectinifera) on the stabilization of Pb, Zn and As in contaminated agricultural soil.

Metal stabilization using soil amendments is an extensively applied, economically viable and environmentally friendly remediation technique. The stabilization of Pb, Zn and As in contaminated soils was evaluated using natural starfish (NSF) and calcined starfish (CSF) wastes at different application rates (0, 2.5, 5.0 and 10.0 wt%). An incubation study was conducted over 14 months, and the efficiency of stabilization for Pb, Zn and As in soil was evaluated by the toxicity characteristic leaching procedure (TCLP) test. The TCLP-extractable Pb was reduced by 76.3-100 and 91.2-100 % in soil treated with NSF and CSF, respectively. The TCLP-extractable Zn was also reduced by 89.8-100 and 93.2-100 % in soil treated with NSF and CSF, respectively. These reductions could be associated with the increased metal adsorption and the formation of insoluble metal precipitates due to increased soil pH following application of the amendments. However, the TCLP-extractable As was increased in the soil treated with NSF, possibly due to the competitive adsorption of phosphorous. In contrast, the TCLP-extractable As in the 10 % CSF treatment was not detectable because insoluble Ca-As compounds might be formed at high pH values. Thermodynamic modeling by visual MINTEQ predicted the formation of ettringite (Ca6Al2(SO4)3(OH)12·26H2O) and portlandite (Ca(OH)2) in the 10 % CSF-treated soil, while SEM-EDS analysis confirmed the needle-like structure of ettringite in which Pb was incorporated and stabilized in the 10 % CSF treatment.

Body burden of persistent organic pollutants on hypertension: a meta-analysis.

Except the known risk factors for hypertension, several studies have suggested that exposure to persistent organic pollutants (POPs), endocrine disrupting chemicals, could be associated with an increased risk of hypertension. In this study, we performed a meta-analysis to summarize the existing epidemiological studies to investigate the association between POPs concentration and risk of hypertension. Based on comprehensive literature search results (PubMed, EMBASE, and KoreaMed), a meta-analysis of 11 articles was performed using a random-effects model. While we observed no significant association between the sum of non-dioxin-like PCBs and the risk of hypertension (OR = 1.00; 95 % CI 0.89, 1.12), the sum of dioxin-like PCBs was associated with a significantly increased risk of hypertension (OR = 1.45; 95 % CI 1.00, 2.12). High p,p'-DDE level was also significantly associated with the increased risk of hypertension. When subgroup analyses were carried out for studies which analyzed POPs concentrations using high-resolution gas chromatography/high-resolution mass spectrometry, the overall pooled estimate ORs increased with decreased heterogeneity, providing it as a possible heterogeneity source (OR = 1.36; 95 % CI 1.21, 1.52; I (2) = 42.8 %; p = 0.045). This study suggested that the concentration of certain POPs, especially dioxin-related compounds, was associated with the risk of hypertension.

Lead and copper immobilization in a shooting range soil using soybean stover- and pine needle-derived biochars: Chemical, microbial and spectroscopic assessments.

Biochar (BC) could be a potential candidate for the remediation of metal contaminated soil. Mechanistic understandings are needed for the appropriate selection of BC and investigating molecular microbial ecological interactions. The soybean stover-derived BCs were more effective in immobilizing Pb (88%) and Cu (87%) than the pine needle-derived BCs in a contaminated shooting range soil. The sequential chemical extractions indicated that BCs stimulated the geochemical transformation of metal species. Spectroscopic investigations using scanning electron microscopic elemental dot mapping and extended X-ray absorption fine structure spectroscopic measurements showed that Pb in the BCs amended soils was immobilized by the formation of stable chloropyromorphite. Soil organic C and microbial activity were also enhanced by BC. The non-labile C fraction in the soil amended with BCs produced at 700°C was increased. Biochars showed less impact on the bacterial community than feedstock biomass as promulgated by the pyrosequencing of 16S rRNA gene. The feedstock type (namely soybean stover and pine needles) was the main factor influencing the BCs efficacy on metals' (im) mobilization and bacterial health in soils.

Chemical stabilisation of lead in shooting range soils with phosphate and magnesium oxide: Synchrotron investigation.

Three Australian shooting range soils were treated with phosphate and magnesium oxide, or a combination of both to chemically stabilize Pb. Lead speciation was determined after 1 month ageing by X-ray absorption spectroscopy combined with linear combination fitting in control and treated soils. The predominant Pb species in untreated soils were iron oxide bound Pb, humic acid bound Pb and the mineral litharge. Treatment with phosphate resulted in substantial pyromorphite formation in two of the soils (TV and PE), accounting for up to 38% of Pb species present, despite the addition of excess phosphate. In MgO treated soils only, up to 43% of Pb was associated with MgO. Litharge and Pb hydroxide also formed as a result of MgO addition in the soils. Application of MgO after P treatment increased hydroxypyromorphite/pyromorphite formation relative to soils teated with phosphate only. X-ray diffraction and Scanning electron microscopy revealed PbO precipitate on the surface of MgO. Soil pH, (5.3-9.3) was an important parameter, as was the solubility of existing Pb species. The use of direct means of determination of the stabilisation of metals such as by X-ray absorption spectroscopy is desirable, particularly in relation to understanding long term stability of the immobilised contaminants.