Heavy metals and arsenic are well-known carcinogens. However, few studies have examined whether soil heavy metals and arsenic concentrations associate with cancer in the general population. In this ecological study, we aimed to evaluate the association of heavy metals and arsenic in soil with cancer mortality rates during 2005–2010 in Suzhou, China, after controlling for education and smoking prevalence. In 2005, a total of 1683 soil samples with a sampling density of one sample every 4 km²were analyzed. Generalized linear model with a quasi-Poisson regression was applied to evaluate the association between town-scale cancer mortality rates and soil heavy metal concentrations. Results showed that soil arsenic exposure had a significant relationship with colon, gastric, kidney, lung, and nasopharyngeal cancer mortality rates and soil nickel exposure was significantly associated with liver and lung cancer. The associations of soil arsenic and nickel exposure with colon, gastric, kidney, and liver cancer in male were higher than those in female. The observed associations of soil arsenic and nickel with cancer mortality rates were less sensitive to alternative exposure metrics. Our findings would contribute to the understanding of the carcinogenic effect of soil arsenic and nickel exposure in general population.

The objective of this paper was to determine the prevalence and sources of high lead (Pb) exposure among children in Bulacan, Philippines. A total of 150 children (6–7 years old) and their caregivers were studied. Lead was analyzed in children hair and deciduous teeth. Sources of lead exposure were determined by caregiver interview and Pb analysis of house soil, drinking faucet water, air, and water from seven Bulacan rivers. Lead was positive in 91.3 % of children’s hair (MC or median concentration = 8.9 μg/g; range = 0–38.29), in 46.2 % of the teeth (MC = 0.000 μg/mg in positive samples; range = 0.00–0.020), in 100 % of soil (MC = 27.06 mg/kg; range = 3.05–1155.80), in 21.1 % of air (MC = 0 μg/Ncm; range = 0–0.10), in 4 % of house, faucet water (MC = 0.0 ppm; range = 0–40). There was a significant correlation (Spearman’s rho) between Pb in children’s hair and soil (r = 0.195; p = 0.017) and between Pb in house water and outdoor air (r = 0.616; p = 0.005). There is no significant correlation between Pb in children’s hair and teeth. None of the potential sources of Pb from interview were related to lead exposure in the children. Water from seven Bulacan rivers was 100 % positive for lead (MC = 70.00 ppb; range = 30–90). Widespread flooding with river overflow occurred in Bulacan in 2009 which likely caused lead contamination of the soil. There was no significant difference in the lead concentration of the soil whether near or far from the river (p = 0.205, Mann-Whitney U test). High lead exposure in children in Bulacan is likely from soil contaminated by lead-polluted rivers during flooding. In areas where flooding is common, alluvial and riparian soils from polluted rivers are important sources of lead exposure in children.

This study aimed at assessing the effect of nitrogen addition under two forms, nitrate and ammonium, on the stabilization of Zn, Pb, and Cd by Populus euramericana Dorskamp grown in contaminated soils for 35 days under controlled conditions. Temporal changes in the soil pore water (SPW) were monitored for pH, dissolved organic carbon (DOC), and total dissolved concentrations of metals in the soils rhizosphere. Rhizospheric SPW pH decreased gradually with NH₄ ⁺ addition and increased with NO₃ ⁻ addition up to one unit, while it slightly decreased initially then increased for the untreated control soil DOC increased with time up to six times, the highest increase occurring with NH₄ ⁺ fertilization. An increase in the metal concentrations in the rhizospheric SPW was observed for NH₄ ⁺ addition associated with the lowest rhizospheric SPW pH, whereas the opposite was observed for the control soil and NO₃ ⁻ fertilization. Fertilization did not affect plant shoots or roots biomass development compared to the untreated control (without N addition). Metals were mostly accumulated in the rhizosphere and N fertilization increased the accumulation for Zn and Pb while Cd accumulation was enhanced for NH₄ ⁺ addition. Collectively, our results suggest metal stabilization by P. euramericana Dorskamp rhizosphere with nitrogen fertilization and are potential for phytostabilization of contaminated technosol.

The purpose of this work was to quantify retention/release of tetracycline, oxytetracycline, and chlortetracycline on two soils, paying attention to sorption kinetics and to implications of the adsorption/desorption processes on transfer of these pollutants to the various environmental compartments. We used the stirred flow chamber (SFC) procedure to achieve this goal. All three antibiotics showed high affinity for both soils, with greater adsorption intensity for soil 1, the one with the highest organic matter and Al and Fe oxides contents. Desorption was always <15 %, exhibiting strong hysteresis in the adsorption/desorption processes. Adsorption was adequately modeled using a pseudo first-order equation with just one type of adsorption sites, whereas desorption was better adjusted considering both fast and slow sorption sites. The adsorption maximum (q ₘₐₓ) followed the sequence tetracycline > oxytetracycline > chlortetracycline in soil 1, with similar values for the three antibiotics and the sequence tetracycline > chlortetracycline > oxytetracycline in soil 2. The desorption sequences were oxytetracycline > tetracycline > chlortetracycline in soil 1 and oxytetracycline > chlortetracycline > tetracycline in soil 2. In conclusion, the SFC technique has yielded new kinetic data regarding tetracycline, oxytetracycline, and chlortetracycline adsorption/desorption on soils, indicating that it can be used to shed further light on the retention and transport processes affecting antibiotics on soils and other media, thus increasing knowledge on the behavior and evolution of these pharmaceutical residues in the environment.

Links between environmental chemicals and human health have emerged, but the effects on mental health such as depression were less studied. Therefore, it was aimed to study the relationships between different sets of urinary environmental chemical concentrations and adult depression in a national and population-based setting in recent years. Data was retrieved from the US National Health and Nutrition Examination Survey in 2011–2012 including demographics, serum measurements, lifestyle factors, self-reported health conditions and urinary chemical concentrations. Depression was determined by using the Patient Health Questionnaire with a cutoff point at 9/10. Chi-square test, t test and survey-weighted logistic regression modeling were performed. Among 5560 American adults aged 20–80 years, 363 (7.8 %) people were classified as having depression (Patient Health Questionnaire score ≥ 10). They tended to have history of health events. After full adjustment including urinary creatinine; demographic characteristics; lifestyle factors; health conditions (such as cardiovascular, neurological, respiratory, digestive and bone diseases, and injury); and subsample weighing; and higher levels of manganese, tin, and phthalates including mono-2-ethyl-5-carboxypentyl, mono-n-butyl, mono-isobutyl, and mono-benzyl were associated with adult depression. Similarly, urinary polyaromatic hydrocarbons including 2-hydroxyfluorene, 3-hydroxyfluorene, 9-hydroxyfluorene, 1-hydroxyphenanthrene, 2-hydroxyphenanthrene, 3-hydroxyphenanthrene, 1-hydroxypyrene, 1-hydroxynaphthalene (1-naphthol), 2-hydroxynaphthalene (2-naphthol) and 4-hydroxyphenanthrene were associated with depression. There were no associations observed in urinary arsenic, phenols, parabens, pesticides, perchlorate, nitrate, thiocyanate and polyfluorinated compounds. Urinary heavy metal, phthalates and polyaromatic hydrocarbons were associated with adult depression, being independent of health events. Further elimination of such harmful chemicals might need to be considered in future mental health and environmental policies.

Sequential anaerobic-aerobic digestion has been demonstrated as a promising alternative for enhanced sludge stabilization. In this paper, a feasibility study of the sequential digestion applied to real waste activated sludge (WAS) and mixed sludge is presented. Process performance is evaluated in terms of total solid (TS) and volatile solid (VS) removal, biogas production, and dewaterability trend in the anaerobic and double-stage digested sludge. In the proposed digestion lay out, the aerobic stage was operated with intermittent aeration to reduce the nitrogen load recycled to the wastewater treatment plant (WWTP). Experimental results showed a very good performance of the sequential digestion process for both waste and mixed sludge, even if, given its better digestibility, higher efficiencies are observed for mixed sludge. VS removal efficiencies in the anaerobic stage were 48 and 50 % for waste and mixed sludge, respectively, while a significant additional improvement of the VS removal of 25 % for WAS and 45 % for mixed sludge has been obtained in the aerobic stage. The post-aerobic stage, operated with intermittent aeration, was also efficient in nitrogen removal, providing a significant decrease of the nitrogen content in the supernatant: nitrification efficiencies of 90 and 97 % and denitrification efficiencies of 62 and 70 % have been obtained for secondary and mixed sludges, respectively. A positive effect due to the aerobic stage was also observed on the sludge dewaterability in both cases. Biogas production, expressed as Nm³/(kgVSdₑₛₜᵣₒyₑd), was 0.54 for waste and 0.82 for mixed sludge and is in the range of values reported in the literature in spite of the low anaerobic sludge retention time of 15 days.

To determine an optimal species pool for periphytic microfauna colonization surveys, a multivariate approach was used to identify the influential species from a raw dataset of periphytic microfauna. Samples were collected at two depths of 1 and 3 m in coastal waters of the Yellow Sea using a glass slide method. From the full 77-species dataset, a 23-species subset with sufficient information of the whole community was identified. The small subset maintained sufficient information of colonization pattern of entire raw communities (correlation coefficient >0.95). The colonization curves based the small subset well fitted the MacArthur-Wilson and logistic model equations in both species composition and individual abundance, respectively. Compared to the functional parameters based on the full dataset, the colonization rates (G) were significantly high and the time reaching 90 % equilibrium species number (T₉₀) significantly low (P < 0.05), while the growth rates (r) and the time reaching 50 % maximum abundance (T₅₀) showed no significant changes (P > 0.05) at both depths, respectively. The species richness, diversity, and evenness represented significantly closed linear relationships between the subset and the full dataset. The results suggest that the small subset might be used as a robust optimal species pool for colonization-based bioassessment surveys and allows developing a time-efficient protocol for marine monitoring programs using of periphytic microfauna.

This study aimed to assess the antibiogram of Aeromonas strains recovered from cattle faeces and the potential pathogenic status of the isolates. The antibiogram of the Aeromonas isolates demonstrated total resistance to clindamycin oxacillin, trimethoprim, novobiocin and ticarcillin. However, Aeromonas strains were sensitive to cefotaxime, oxytetracycline and tobramycin. The Aeromonas strains from Lovedale and Fort Cox farms were found to possess some virulence genes. The percentage distribution was aer 71.4 %, ast 35.7 %, fla 60.7 %, lip 35.7 % and hlyA 25 % for Lovedale farm and aer 63.1 %, alt 10.5 %, ast 55.2 %, fla 78.9 %, lip 21 % and hlyA 35.9 % for Fort Cox farm. Class 1 integron was present in 27 % of Aeromonas isolates; the bla TEM gene was present in 34.8 %, while the blaP1 class A β-lactamase gene was detected in 12.1 % of the isolates. Approximately 86 % of the isolates formed a biofilm on microtitre plates. The presence of multiple antibiotic resistance and virulence genes in Aeromonas isolates from cattle faeces reveals the pathogenic and infectious importance of these isolates and is of great significance to public health. The possession of a biofilm-forming capability by such isolates may lead to difficulty during the management of infection related to Aeromonas species.

The characteristics of volatile organic compounds (VOCs) emitted from several consumer and commercial products (body wash, dishwashing detergent, air freshener, windshield washer fluid, lubricant, hair spray, and insecticide) were studied and compared. The spray products were found to emit the highest amount of VOCs (~96 wt%). In contrast, the body wash products showed the lowest VOC contents (~1.6 wt%). In the spray products, 21.6–96.4 % of the VOCs were propane, iso-butane, and n-butane, which are the components of liquefied petroleum gas. Monoterpene (C₁₀H₁₆) was the dominant component of the VOCs in the non-spray products (e.g., body wash, 53–88 %). In particular, methanol was present with the highest amount of VOCs in windshield washer fluid products. In terms of the number of carbon, the windshield washer fluids, lubricants, insecticides, and hair sprays comprised >95 % of the VOCs in the range C₂–C₅. The VOCs in the range C₆–C₁₀ were predominantly found in the body wash products. The dishwashing detergents and air fresheners contained diverse VOCs from C₂ to C₁₁. Besides comprising hazardous VOCs, VOCs from consumer products were also ozone precursors. The ozone formation potential of the consumer and commercial spray products was estimated to be higher than those of liquid and gel materials. In particular, the hair sprays showed the highest ozone formation potential.

Despite decades of intensive research, lead (Pb) toxicity still remains one of the most frequently investigated subjects in environmental health. Whole blood lead (BPb) is usually used to evaluate Pb exposure for both screening and clinical diagnosis. However, it is generally recognized that BPb is not a sensitive biomarker for Pb exposure in hematological studies. Considering hematocrit (HCT) variation in different situations, HCT-adjusted BPb or erythrocyte Pb (EPb) may be more relevant when evaluating the hematotoxicity of blood Pb. Data collected from 855 preschool children, 3–7 years of age, allowed us to examine the relationship between EPb and hemoglobin (Hb) levels. Multivariate linear regression was performed to determine the significance of EPb as predictor of Hb after covariate adjustment; then, mean differences of Hb levels between quartiles of EPb and BPb (1st quartile as reference) were determined using ANOVA followed by Student’s t test. The dose-response curve between EPb and HCT was plotted using locally weighted scatterplot smoothing (LOWESS) method. A doubling of EPb was associated with a 2.44 g/L decrease in Hb level. Compared to the 1st quartile group of EPb, the 3rd and 4th quartile groups showed significant decreases in Hb levels (3.01 and 3.97 g/L, respectively). Compared to the 1st quartile group of BPb, the 2nd quartile group showed a decrease in Hb levels (0.63 g/L), while the 3rd and 4th quartile groups showed increases in Hb levels (0.78 and 1.45 g/L, respectively). Increased EPb levels are significantly associated with decreased Hb levels in preschool children. HCT must be taken into consideration in investigating the hematological effects of Pb. Compared to BPb, EPb or HCT-adjusted BPb appear as a more effective biomarker to interpret the hematotoxicity of lead. Furthermore, blood erythrocytes are not only a repository of Pb but also a primary target of its toxicity.