PBDD/Fs in Surface Sediments from the East River,China

The contamination status of polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) was preliminarily investigated in surface sediments from the East River. The concentrations of eight 2,3,7,8-substituted tetra- to hexa- PBDD/Fs were found to be in the range of 0.32–110 (mean 13) pg g⁻¹ and the corresponding TEQ concentrations were 0.087–18 (mean 2) pg I-TEQ g⁻¹. All sediments were characterized by the dominant PBDFs. 2,3,4,7,8-PeBDF was the most important TEQ contributor, accounting for 47%–77% of the total I-TEQ of PBDD/Fs. PCDD/Fs contributed dominantly to the total TEQs of PCDD/Fs, PBDD/Fs and dioxin-like PCBs in most samples except of the sediment from the Shima River. The higher PBDD/F concentrations in the Shima River may be attributed to the use of BFRs in the electrical and electronics industries, which posed a potential risk of dioxins on ecological system.     

Levels and Congener Profiles of Particle-bound Polybrominated Dibenzo-<Emphasis Type="Italic">p</Emphasis>-dioxins/furans (PBDD/Fs) in Ambient Air around Guangzhou,China

The mean particulate polybrominated dibenzo-p-dioxins/furans (PBDD/Fs) levels for Guangzhou were in the range of 225–2244 fg/m³ and showed the spatial trend of background < suburb areas < urban area < industrial area, suggesting the industrial and urban sources of PBDD/Fs. The most abundant congeners were 2,3,7,8-TBDF, 1,2,3,7,8-PeBDF and 2,3,4,7,8-PeBDF. The mean toxicity equivalency quantities (TEQs) of PBDD/Fs were in the range of 89.3–456 fg I-TEQ/m³ for Guangzhou, which were several times higher than that of the background area (49.1 fg I-TEQ/m³). The rough inhalation risk evaluation showed that the residents in Guangzhou were in relatively higher exposure levels of PBDD/Fs.     

Atmospheric concentrations of PCDD/Fs,PAHs, and metals in the vicinity of a cement plant in Istanbul

The levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polycyclic aromatic hydrocarbons (PAHs), and metals (Al, As, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Tl, V, and Zn) in particulate matter (PM10) were determined in ambient air at selected two sampling points located under the influence of a cement plant and a background/control sampling point in Büyükçekmece Istanbul. The samplings of PM10, PCDD/Fs, and PAHs were carried out simultaneously from September 2011 to November 2012 with EN 12384, EPA TO-9A, and EPA TO-13A, respectively. Quartz-fiber filters and glass adsorbent cartridge containing the polyurethane foam (PUF) are installed in air sampler for PAHs and PCDD/Fs sampling. The mean concentrations of PCDD/Fs in SP-1, SP-2, and SP-3 (control point) were 5.5?±?1.7 fg I-TEQ m^?3, 8.5?±?2.6 fg I-TEQ (International Toxic Equivalents)?m^?3, and 0.2?±?0.1 fg I-TEQ m^?3, respectively. The higher PAHs and BaP concentrations during winter were probably due to increasing emissions from residential heating. Ca, Mg, Al, Fe, K, and Na showed elevated concentration values compared to other metals, with mean values of 10,401?±?1,050 and 3,934?±?397, 473?±?43 and 301?±?27, 1,478?±?177 and 1,465?±?176, 1,168?±?151 and 934?±?121, 700?±?69 and 1,380?±?137, and 1,181?±?94 and 434?±?35 ng m^?3 in the sampling and control points, respectively. The results of principal component analysis (PCA) and Pearson correlation analysis were consistent with those of literature for similar areas and showed a clear distinction between the sampling points and the source profiles. The ambient air concentrations of PCDD/Fs, PAHs, and metals in the vicinity of a cement plant were presented for the first time in Turkey through this work.     

Evidence of PCDD/Fs and PCBs Contamination in Trees Grown in Forests Far from Their Production and Contamination-Free Areas

Polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) in trees grown in pathless forests were analyzed to investigate their dispersal patterns in the atmosphere. The pg/g levels of 23 PCCD, 22 PCDF, and 54 PCB congeners were identified. The total amount of PCDDs in the red pine tree sample (95.8 pg/g) was approximately 7 times that in the beech tree sample (13.2 pg/g). The total amount of PCDFs in the red pine tree sample (71.1 pg/g) was also approximately 7 times that in the beech tree sample (11.1 pg/g). The total amounts of PCBs in the red pine tree and beech tree samples were 1,380 and 1,150 pg/g, respectively. The (Cl₁–Cl₃)-PCBs comprised 63.1 % and 67.6 % of total PCBs in the red pine and in the beech, respectively. The results of the present study indicate that PCDD/Fs and PCBs are transferred over long distances in the atmosphere and accumulated in the contamination-free areas.     

Retention and maternal transfer of environmentally relevant polybrominated dibenzo-p-dioxins and dibenzofurans, polychlorinated dibenzo-p-dioxins and dibenzofurans, and polychlorinated biphenyls in zebrafish (Danio rerio) after dietary exposure

High levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), mono- and non-ortho-polychlorinated biphenyls (PCBs), and polybrominated dibenzo-p-dioxins (PBDDs) are found in fish from coastal areas in the Baltic Sea, which may cause ecotoxicological effects. To increase our understanding of the persistency of the emerging pollutants polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs), fish feed was spiked with 21 PBDD/Fs, 17 PCDD/Fs, and 30 PCBs and fed to zebrafish (Danio rerio). Concentrations in fish and eggs were examined during a 6- or 12-week uptake period, and a 6-week elimination period. Steady-state was reached for 2-, 3-, 7-, and/or 8-substituted tri- and tetra-BDD/Fs; 2,3,7,8-tetra-BDD (2,3,7,8-TeBDD) was the most strongly retained. Steady-state was not reached for tetra- to hexa-CDDs. Non-2,3,7,8 congeners showed little or no retention. Most PCBs had high retention and did not reach steady state. Half-lives decreased in the order PCBs?>?PCDD/Fs?>?PBDD/Fs. Concentrations of 2,3,7,8-substituted penta- to octa-CDD/Fs decreased with their degree of chlorination, suggesting that the rate-limiting factor for uptake is low bioavailability. Maternal transfer was observed for all retained compounds, with most transfer factors <1, indicating that transfer rates are affected by the poor water solubility of the compounds. The limited retention of the major PBDD congeners found in Baltic Sea fish suggests that they are exposed to high or very high concentrations via either food or water.     

Comparison of Historical Record of PCDD/Fs, Dioxin-Like PCBs, and PCNs in Sediment Cores from Jiaozhou Bay and Coastal Yellow Sea: Implication of Different Sources

The concentrations of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs), dioxin-like polychlorinated biphenyls (PCBs), and polychlorinated naphthalenes (PCNs) were measured in two sediment cores collected from Jiaozhou Bay. The concentrations of PCDD/Fs, dioxin-like PCBs, and PCNs in the cores were in the range of 2.8–26.3, 7.1–82.4 and 3.9–56.4 pg/g dw, respectively. The depth profiles of total concentrations PCDD/Fs and dioxin-like PCBs were similar in the sediment core J37 inside Jiaozhou Bay, but different from those in the sediment core J94 outside the bay, suggesting the different sources. In both cores Tri-CNs and Tetra-CNs were dominant, similar to the PCNs composition of some Halowax technical products. The maximal PCNs contamination occurred in the mid-1970s (outside the Bay) and early-1990s (inside the Bay). An increase of the indicator CN congeners characteristic for thermal source in the top layers of the sediment core inside the bay indicated that the contribution from the municipal solid waste incineration has been more important in recent years.     

The relative contribution of individual polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzo-p-furans (PCDFs) to toxic equivalent values derived for bulked human adipose tissue samples from Wales,United Kingdom

Five bulked human adipose tissue samples were analyzed for individual polychlorinated biphenyl (PCB) congeners (including selected non-ortho-substituted compounds) and polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs). Mean PCB and PCDD/F (tetra-through octachlorinated homologues) concentrations were 0.75 g/g and 1.22 ng/g adipose tissue respectively. Both the congener patterns and levels detected were similar to those reported by laboratories in other industrialised countries. Each sample comprised of tissue taken from donors within a given locality. However, no obvious relationships were apparent between sampling area, absolute concentrations and congener pattern of PCBs and PCDD/Fs.The contribution of individual PCDD/F and non -ortho-(o), mono-o-, and di-o-substituted PCB congeners to the total calculated toxic equivalent values (TEQ) was assessed for each sample. The main contributions to the TEQ were the mono-o-substituted PCB congeners #118 (TEQ=42.5 pg/g of lipid), #156 (TEQ=24.8 pg/g) and #105 (TEQ=20.7 pg/g), followed by 1,2,3,6,7,8-HxCDD (TEQ=18.2 pg/g), 2,3,4,7,8-P₅CDF (TEQ= 12 pg/g), 1,2,3,7,8-P₅CDD (TEQ=11.5 pg/g), and the non-o-substituted PCB congener #126 (TEQ =11.3 pg/g). Collectively, these compounds accounted for 80% of the STEQ values. Based on the TEFs proposed by Safe (1990), the overall TEQs calculated for the monitored PCBs, were twice those due to PCDD/Fs.     

The Influence of Pregnancy on Sweet Taste Perception and Plaque Acidogenicity

Objectives Women undergo different physiological and oral changes during pregnancy and this may increase the risk of dental caries and other oral diseases. The aim of the present study was to investigate changes in biofilm acidogenicity and correlate them to sweet taste perception in pregnant and non-pregnant women. Methods Three groups of Saudi women participated in this cross-sectional study: (1) women in early pregnancy (n?=?40/mean age 29.6 years/DMFT 10.7), (2) women in late pregnancy (n?=?40/29.5 years/DMFT 10.8) and (3) non-pregnant women (n?=?41/27.7 years/DMFT 12.3). Changes in plaque pH were determined by using colour-coded indicator strips before and after a 1-min rinse with a 10% sucrose solution. A taste perception test determining sweet preference and threshold levels was also performed. Results A significant difference regarding plaque pH was seen between the early, late and non-pregnant women when calculated as the area under the curve (p?<?0.05). Regarding the taste perception tests, taste preference and threshold were correlated (p?<?0.001, r?=?0.6). Between the three groups, a statistically significant difference was seen in taste threshold and taste preference respectively (p?=?0.001 and p?<?0.001). Conclusions The findings in this study suggest that pregnant women may undergo taste changes and experience lower plaque pH, which may result in an increased risk of dental caries.     

Do Human Milk Concentrations of Persistent Organic Chemicals Really Decline During Lactation? Chemical Concentrations During Lactation and Milk/Serum Partitioning

Background

Conventional wisdom regarding exposures to persistent organic chemicals via breast-feeding assumes that concentrations decline over the course of lactation and that the mother’s body burden reflects her cumulative lifetime exposure. Two important implications stemming from these lines of thought are, first, that assessments of early childhood exposures should incorporate decreasing breast milk concentrations over lactation; and, second, that there is little a breast-feeding mother can do to reduce her infant’s exposures via breast-feeding because of the cumulative nature of these chemicals.

Objectives

We examined rates of elimination and milk/serum partition coefficients for several groups of persistent organic chemicals.

Methods

We collected simultaneous milk and blood samples of 10 women at two times postpartum and additional milk samples without matching blood samples.

Results

Contrary to earlier research, we found that lipid-adjusted concentrations of polybrominated diphenyl ethers, polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins and furans, and organochlorine pesticides in serum and milk do not consistently decrease during lactation and can increase for some women. Published research has also suggested an approximate 1:1 milk/serum relationship (lipid adjusted) on a population basis for 2,3,7,8-tetrachlorodibenzo-p-dioxin; however, our results suggest a more complex relationship for persistent, lipophilic chemicals with the milk/serum relationship dependent on chemical class.

Conclusions

Decreases in concentration of lipophilic chemicals on a lipid-adjusted basis during lactation should no longer be assumed. Thus, the concept of pumping and discarding early milk as means of reducing infant exposure is not supported. The hypothesis that persistent lipophilic chemicals, on a lipid-adjusted basis, have consistent concentrations across matrices is likely too simplistic.     

Persistent misconceptions about HIV transmission among males and females in Malawi

Background

The prevalence of HIV in Malawi is one of the highest in sub-Saharan Africa, and misconceptions about its mode of transmission are considered a major contributor to the continued spread of the virus.

Methods

Using the 2010 Malawi Demographic and Health Survey, the current study explored factors associated with misconceptions about HIV transmission among males and females.

Results

We found that higher levels of ABC prevention knowledge were associated with lower likelihood of endorsing misconceptions among females and males (OR?=?0.85, p?<?0.001; OR?=?0.85, p?<?0.001, respectively). Compared to those in the Northern region, both females and males in the Central (OR?=?0.54, p?<?0.001; OR?=?0.53, p?<?0.001, respectively) and Southern regions (OR?=?0.49, p?<?0.001; OR?=?0.43, p?<?0.001, respectively) were less likely to endorse misconceptions about HIV transmission. Moreover, marital status and ethnicity were significant predictors of HIV transmission misconceptions among females but not among males. Also, household wealth quintiles, education, religion, and urban–rural residence were significantly associated with endorsing misconceptions about HIV transmission.

Conclusion

Based on our findings, we recommend that education on HIV transmission in Malawi should integrate cultural and ethnic considerations of HIV/AIDS.

     

Occurrence,Human Exposure,and Risk Assessment of Polybrominated Dibenzo-p-Dioxins and Dibenzofurans,Polychlorinated Naphthalenes,and Metals in Atmosphere Around Industrial Parks in Jiangsu,China

Air samples were collected around industrial parks in Jiangsu, China, to allow the concentrations, profiles, and risk assessment of polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs), polychlorinated naphthalenes (PCNs), and metals to be investigated. The concentrations of ΣPBDD/Fs and ΣPCNs were 1324.26–2080.98 fg/m³ (11.35–42.57 fg I-TEQ/m³) and 10,404.9–29,322.9 fg/m³ (1.32–7.19 fg I-TEQ/ m³), respectively. The highest concentration of ΣPBDD/Fs and ΣPCNs were observed at site C. PBDD/Fs were mainly dominated by PBDFs. The main contributor to the ΣPBDD/Fs in all samples was 1,2,3,4,6,7,8-HpBDF, which accounted for 25.75%–39.4%. For PCNs, the predominating homologues were tetra-, tri- and penta-CNs, which contributed 30.7%–43.3%, 24.7%–31.0%, and 10.6%–21.6%, respectively. As for metals, the pollution of As, Mn, Cr, and Ni in most samples exceeded National Ambient Air Quality Standards of China. Assessing the risk of inhalation exposure showed that there were potential carcinogenic risks to local residents.

     

PCDD/Fs in Soil Samples Collected in the Vicinity of a Municipal Solid Waste Incinerator: Human Health Risks

The concentrations of polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) were determined in soil samples taken from 24 sites in the vicinity of a municipal solid waste incinerator (Montcada, Barcelona, Spain). Samples were collected within a radius of 3 km in each of the three main directions of the wind rose in that area. Hepta- and octa-CDDs were the predominant congeners and contributors to TEQ. PCDD/F levels ranged from 0.30 to 44.26 ng TEQ/kg (dry matter), with median and mean values of 3.52 and 6.91 ng TEQ/kg, respectively. The highest and lowest PCDD/F concentrations were found at 750 m (44.26 ng TEQ/kg) and 3000 m (0.30 ng TEQ/kg) from the stack, while the PCDD/PCDF ratio was 1.78. The health risk analysis of the data shows that the PCDD/F intake from soils is substantially lower than the tolerable daily intake for toxicologic (other than cancer) effects of PCDD/Fs. Received: 18 April 1997/Accepted: 15 July 1997     

The relationship between dioxins and salivary steroid hormones in Vietnamese primiparae

Objective

Nearly 40 years after Agent Orange was last sprayed, we conducted a cross-sectional study to evaluate the impact of dioxin exposure on salivary hormones in Vietnamese primiparae. Our previous studies found higher levels of salivary cortisol and cortisone in one of the most highly dioxin-contaminated areas, known as a “hot-spot”, than in a non-exposed area. As a result, we suggested that further research with a larger number of participants would be needed to confirm whether dioxin affects steroid hormone levels in Vietnamese primiparae.

Methods

The concentration of steroid hormones in saliva was determined by liquid chromatography (electrospray ionization tandem mass spectrometry), whereas the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) in breast milk were determined by gas chromatography-high resolution mass spectrometry, for a sample of the population from a “hot-spot” (n = 16) and a non-exposed area (n = 10). All subjects were aged between 20 and 30 years and had children aged between 4 and 16 weeks.

Results

The mean toxic equivalence of PCDDs, PCDFs and PCDDs + PCDFs in breast milk in the hot-spot area was found to be significantly higher than in the non-exposed area (p < 0.001). Likewise, salivary cortisol, cortisone and dehydroepiandrosterone (DHEA) levels were significantly higher in the hotspot area than in the non-exposed area (p < 0.05). As a result, herein we report, for the first time, that salivary DHEA levels in primiparae are higher in a hot-spot than in a non-exposed area, and that this may be the result of dioxin exposure.

Conclusions

Our findings highlight the long-term effects of Agent Orange/dioxin on steroid hormones in Vietnamese primiparae in the post-war period.

     

Levels of PCDD/Fs,Dl-PCBs and HCB in Air,Soils and Sediments from a City with Multiple Thermal-Related Industries in China

The levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), dioxin-like polychlorinated biphenyls (dl-PCBs) and hexachlorobenzene (HCB) were measured in various environmental compartments in Tangshan, China, which contains multiple thermal-related industries. The total toxic equivalent concentrations of these pollutants were 138 ± 87.2 fg/m³ in air, 3.43 ± 2.88 pg/g in soils, and 1.42 ± 1.5 pg/g in sediments. The 2,3,7,8-PCDD/Fs profiles in atmospheric samples suggest that thermal-related industries are the most likely potential sources. Of the dl-PCBs, CB-77, CB-105 and CB-118 were the most abundant congeners and CB-126 was the dominant contributor to the TEQs from the dl-PCBs.     

A Test of Outreach and Drop-in Linkage Versus Shelter Linkage for Connecting Homeless Youth to Services

Outreach and service linkage are key for engaging marginalized populations, such as homeless youth, in services. Research to date has focused primarily on engaging individuals already receiving some services through emergency shelters, clinics, or other programs. Less is known about those who are not connected to services and, thus, likely the most vulnerable and in need of assistance. The current study sought to engage non-service-connected homeless youth (N?=?79) into a strengths-based outreach and advocacy intervention. Youth were randomly assigned to receive 6 months of advocacy that focused on linking youth to a drop-in center (n?=?40) or to a crisis shelter (n?=?39). All youth were assessed at baseline and 3, 6, and 9 months post-baseline. Findings indicated that youth prefer drop-in center services to the shelter. Also, the drop-in center linkage condition was associated with more service linkage overall (B?=?0.34, SE?=?0.04, p?<?0.01) and better alcohol-l [B?=??0.39, SE?=?0.09, t(75)?=??4.48, p?<?0.001] and HIV-related outcomes [B?=?0.62, SE?=?0.10, t(78)?=?6.34, p?<?0.001] compared to the shelter linkage condition. Findings highlight the importance of outreach and service linkage for reconnecting service-marginalized youth, and drop-in centers as a primary service option for homeless youth.     

Persistent Organochlorine Contaminant Residues in Tissues of Hedgehogs from Turkey

The residues of persistent organochlorinated pollutants (POPs), namely polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) (HCHs, CHLs, HCCPs, DDTs, and dicofol congeners) were investigated in the hair and muscle of road-killed Erinaceus roumanicus and E. concolor in Turkey. Mean residue levels were as follows: in hair, PCBs?=?7.43?±?4.88 ng/g and OCPs?=?9.21?±?1.27 ng/g; in muscle, PCBs?=?30.73?±?2.51 ng/g and OCPs?=?145.04?±?16.59 ng/g. There was no significant difference between species and sex, while there was significant difference between habitats and regions in terms of either total PCB and OCP levels, or POP levels (p?<?0.05). Age was a determinative factor for the bio-accumulation of POPs. The contaminant levels were high in the species, sample areas, and habitats. The data also showed that tissues of hedgehogs are suitable for monitoring and evaluating the bioaccumulation of POP levels in Turkey.     

Sleep apnoea in Australian men: disease burden,co-morbidities,and correlates from the Australian longitudinal study on male health

Background

Obstructive sleep apnoea is a common disorder with under-rated clinical impact, which is increasingly being recognised as having a major bearing on global disease burden. Men are especially vulnerable and become a priority group for preventative interventions. However, there is limited information on prevalence of the condition in Australia, its co-morbidities, and potential risk factors.

Methods

We used data from 13,423 adult men included in the baseline wave of Ten to Men, an Australian national study of the health of males, assembled using stratified cluster sampling with oversampling from rural and regional areas. Those aged 18–55 years self-completed a paper-based questionnaire that included a question regarding health professional-diagnosed sleep apnoea, physical and mental health status, and health-related behaviours. Sampling weights were used to account for the sampling design when reporting the prevalence estimates. Odds ratios were used to describe the association between health professional-diagnosed sleep apnoea and potential correlates while adjusting for age, country of birth, and body-mass index (BMI).

Results

Prevalence of self-reported health professional-diagnosed sleep apnoea increased from 2.2 % in age 18–25 years to 7.8 % in the age 45–55 years. Compared with those without sleep apnoea, those with sleep apnoea had significantly poorer physical, mental, and self-rated health as well as lower subjective wellbeing and poorer concentration/remembering (p?<?0.001 for all). Sleep apnoea was significantly associated with older age (p?<?0.001), unemployment (p?<?0.001), asthma (p?=?0.011), chronic obstructive pulmonary disease/chronic bronchitis (p?=?0.002), diabetes (p?<?0.001), hypercholesterolemia (p?<?0.001), hypertension (p?<?0.001), heart attack (p?<?0.001), heart failure (p?<?0.001), angina (p?<?0.001), depression (p?<?0.001), post-traumatic stress disorder (p?<?0.001), other anxiety disorders (p?<?0.001), schizophrenia (p?=?0.002), overweight/obesity (p?<?0.001), insufficient physical activity (p?=?0.006), smoking (p?=?0.005), and high alcohol consumption (p?<?0.001).

Conclusion

Health professional-diagnosed sleep apnoea is relatively common, particularly in older males. Associations between sleep apnoea and cardiovascular, metabolic, respiratory, and psychiatric disorders have important clinical and public health implications. As men are especially vulnerable to sleep apnoea as well as some of its chronic co-morbidities, they are potentially a priority group for health interventions. Modifiable lifestyle related factors such as smoking, alcohol consumption, level of physical activity and BMI are possible key foci for interventions.

     

The use of PowerPrep and HRGC/HRMS for biological monitoring of exposure to PCDD,PCDF and dl-PCB in Poland

Purpose

The aim of this study was to design the optimized laboratory protocol as a tool for human biomonitoring of selected Persistent Organic Pollutants (POPs) in Poland. In this study, we present the method developed for the determination of 29 congeners of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs), as well as individual results of the measurements in 40 human breast milk samples collected in central Poland in 2008–2010.

Methods

The protocol of sample preparation and quantitative analysis of PCDD/Fs and dl-PCBs was optimized for the isotopic dilution method with high resolution gas chromatography/high resolution mass spectrometry HRGC/HRMS. Fat content in the extracts was determined gravimetrically. The results were corrected by fat content in the samples.

Results

The average sum of PCDD/F and dl-PCBs in the human milk samples from the urban area was 7.429 WHO-TEQ pg/g fat (with the range 0.431–14.27), and in the rural area it was 6.448 pg WHO-TEQ/g fat (0.539–12.61).

Conclusions

The results obtained in this study indicate that the mothers were exposed uniformly to PCDD/Fs and PCBs regardless of location. The significant difference of p < 0.1 between the milk samples from the urban and rural mothers in 2,3,7,8-TCDD; 1,2,37,8,9-HxCDD and 2,3,4,6,7-HxCDF were observed. For the other 14 PCDD/F and 12 dl-PCB congeners, the observed differences were not significant. The total WHO-TEQ values are lower in comparison with the average results in Europe from the fourth round of a WHO-coordinated study.     

The Influence of Home and School Environments on Children’s Diet and Physical Activity,and Body Mass Index: A Structural Equation Modelling Approach

Introduction The home and school environments play important roles in influencing children’s health behaviours. However, their simultaneous influence on childhood obesity has not yet been examined. We explore the relationship of the home and school environments with childhood obesity, to determine whether this relationship is mediated by children’s fruit and vegetable intake and physical behaviours. Methods This study uses baseline data from 9 to 11 year old children, their parents and school principals (matched data n?=?2466) from the Obesity Prevention and Lifestyle Project. Child-reported behaviours, parent-reported home environment and principal-reported school environment data were collected via questionnaires. Trained researchers measured children’s height and weight, and Body Mass Index (BMI, kg/m²) was calculated. Structural equation modelling was used to assess the relationship of the home and school environments with children’s fruit and vegetable intake, physical activity behaviours, and children’s BMI. Result The home diet environment was positively associated with child diet (β?=?0.18, p?<?0.001). The home physical activity environment had the largest inverse association with BMI (β?=???0.11, p?<?0.001), indirectly through child physical activity (β?=?0.28 ,p?<?0.001). Schools’ healthy eating policy implementation was significantly associated with child diet (β?=?0.52, p?<?0.05), but physical activity policy was not associated with child activity (β?=???0.007, p?>?0.05). The school environment was not associated with child BMI. Discussion The home environment had a stronger association with healthier child behaviours, compared to the school environment. These findings suggest that future childhood obesity interventions targeting healthier home environments and supporting parents can promote healthier child eating and physical activity behaviours.