Toxicity of Chiral Pesticide <Emphasis Type="Italic">Rac-</Emphasis>Metalaxyl and <Emphasis Type="Italic">R-</Emphasis>Metalaxyl to <Emphasis Type="Italic">Daphnia magna</Emphasis>

Chirality in pesticides has become a challenge because of enantiomers’ different toxicities to non-target organisms. Acute and chronic toxicities of Rac-metalaxyl and R-metalaxyl to Daphnia magna were determined and compared. The 48-h LC50 for Rac- and R-metalaxyl to Daphnia magna were 51.5 and 41.9 mg/L. In a 14-day chronic test, the lowest-observed-effective concentration (LOEC) and no-observed-effective concentration (NOEC) of Rac-metalaxyl were 2 and 1 mg/L, respectively, whereas those of R-metalaxyl were 1 and 0.1 mg/L. Body length, days-to-first-brood and number of broods per female were significantly (p < 0.05) affected by R-metalaxyl at >1.0 mg/L, but affected by Rac-metalaxyl at ≥2.0 mg/L.     

Effects of Pentachlorophenol on <Emphasis Type="Italic">Galba pervia</Emphasis>, <Emphasis Type="Italic">Tubifex sinicus</Emphasis> and <Emphasis Type="Italic">Chironomus plumousus</Emphasis> Larvae

The 24-h median lethal concentrations of pentachlorophenol to Chironomus plumousus, Tubifex sinicus and Galba pervia were 0.302, 0.977 and 0.293 mg/L, respectively. Bioconcentration factors of C. plumousus, T. sinicus and G. pervia to pentachlorophenol were 108, 367 and 85 at 0.02 mg/L pentachlorophenol, respectively. As pentachlorophenol concentration increased, the G. pervia egg hatching rates became lower, and the total hatched time became longer. Pentachlorophenol teratogenesis was demonstrated by observing the deformation of C. plumousus larvae mentum.     

Copper Accumulation and Tolerance in <Emphasis Type="Italic">Chrysanthemum coronarium</Emphasis> L. and <Emphasis Type="Italic">Sorghum</Emphasis><Emphasis Type="Italic">sudanense</Emphasis> L.

In the present study, the growth of Chrysanthemum coronarium L. and Sorghum sudanense L. and their copper accumulation were studied using hydroponic experiments. Results showed that the root elongation, dry biomass yield, and chlorophyll content in both plant species decreased significantly with the increasing level of Cu in solution. The concentrations of Cu in the two plants increased greatly with the increasing Cu level in the treatments. However, most of the Cu was accumulated in roots, and only a small portion was translocated into shoots. Compared with S. sudanense, the shoots of C. coronarium had a significantly higher concentration of Cu. The total amount and percentage of water-soluble Cu, and the nonprotein thiol were also higher in the shoots of C. coronarium. In the roots, however, S. sudanense accumulated more Cu than C. coronarium. The treatments with 5 to 50 μmol L⁻¹ Cu significantly increased the uronic acid content in the roots of S. sudanens, but did not have any significant effect for C. coronarium. Higher concentrations of Cu bound to the cell wall and uronic acid in the roots of S. sudanense were speculated to be the main reason to restrain Cu translocation from roots to shoots.     

Allelopathic Effects of <Emphasis Type="Italic">Myriophyllum aquaticum</Emphasis> on Two Cyanobacteria of <Emphasis Type="Italic">Anabaena flos-aquae</Emphasis> and <Emphasis Type="Italic">Microcystis aeruginosa</Emphasis>

Allelopathy has been proposed as a sustainable means to control undesired algal growth and to reduce blooms threatening freshwater systems worldwide. In this study, the allelopathic effects of Myriophyllum aquaticum and its exudate on two typical bloom-forming cyanobacteria, Microcystis aeruginosa and Anabaena flos-aquae, were investigated under laboratory conditions. The growth of the cyanobacteria was strongly inhibited by live M. aquaticum while the primary addition of M. Aquaticum exudates had a significant inhibitory effect on the growth of M. aeruginosa but not A. flos-aquae. The results suggested that the persistent release of allelochemicals from live M. aquaticum was needed to effectively constrain the growth of A. flos-aquae. Analysis of cyanobacterial physiological indexes indicated that M. aquaticum produced an inhibitory effect on SOD enzyme activity of A. flos-aquae, while it affected membrane lipid peroxidation in M. aeruginosa. The results show the potential of M. aquaticum to mitigate cyanobacterial blooms in coexistence systems.     

<Emphasis Type="Italic">Chlamydia</Emphasis><Emphasis Type="Italic">trachomatis</Emphasis> and placental inflammation in early preterm delivery

Chlamydia trachomatis may infect the placenta and subsequently lead to preterm delivery. Our aim was to evaluate the relationship between the presence of Chlamydia trachomatis and signs of placental inflammation in women who delivered at 32 weeks gestation or less. Setting: placental histology and clinical data were prospectively obtained from 304 women and newborns at the Erasmus MC-Sophia, Rotterdam, the Netherlands. C. trachomatis testing of placentas was done retrospectively using PCR. C. trachomatis was detected in 76 (25%) placentas. Histological evidence of placental inflammation was present in 123 (40%) placentas: in 41/76 (54%) placentas with C. trachomatis versus 82/228 (36%) placentas without C. trachomatis infection (OR 2.1, 95% CI 1.2–3.5). C. trachomatis infection correlated with the progression (P = 0.009) and intensity (P = 0.007) of materno-fetal placental inflammation. C. trachomatis DNA was frequently detected in the placenta of women with early preterm delivery, and was associated with histopathological signs of placental inflammation.     

Comparative Studies on the Toxicokinetics of Benzo[<Emphasis Type="Italic">a</Emphasis>]pyrene in <Emphasis Type="Italic">Pinctada martensii</Emphasis> and <Emphasis Type="Italic">Perna viridis</Emphasis>

Research on the kinetics of Benzo[a]pyrene (B[a]P) bioaccumulation in the clam Pinctada martensii and mussel Perna viridis showed that the initial rate of uptake was directly related to the PAH concentrations in the ambient environment. The uptake and depuration rate constants were different at the four B[a]P exposure levels, which indicated that the toxicokinetic rate constants mainly depended on the exposure levels of pollutants to the environment. In addition, the uptake rate constants of B[a]P were higher than the depuration rate constants in the entire experiment. The comparison demonstrated that mussels release B[a]P more rapidly than clams. The bioconcentration factors (BCFs) of B[a]P varied from 3335 to 12892 in the clam and 2373–6235 in the mussel. These findings on the bioaccumulation kinetics for petroleum hydrocarbons, in association with the critical body residue, will be valuable when choosing sensitive organisms to assess the potential ecotoxicological risk to the marine environment.     

Chronic Effects of <Emphasis Type="Italic">Pinus radiata</Emphasis> and <Emphasis Type="Italic">Eucalyptus globulus</Emphasis> Kraft Mill Effluents and Phytosterols on <Emphasis Type="Italic">Daphnia magna</Emphasis>

Two kraft pulp mill effluents were compared in terms of their chronic toxicity to Daphnia magna. One resulted from pulping Pinus radiata and the other came from a parallel processing of Pinus radiata and Eucalyptus globulus (mixed kraft pulp mill effluent). The concentration of phytosterols found in the mixed kraft pulp mill effluent was higher than in the effluent from Pinus radiata, with values of 0.1082 and 0.02 μg/L, respectively. The phytosterols per se are responsible for 12.9% and 8.1% of the deviation from the natural shape, while the kraft pulp mill effluents account for 25.6%–27.8% of shape deviation. The role of β-sitosterol and stigmasterol is discussed in relation to endocrine disruption.     

Toxicity of Sediment-Associated Pesticides to <Emphasis Type="Italic">Chironomus dilutus</Emphasis> and <Emphasis Type="Italic">Hyalella azteca</Emphasis>

Two hundred sediment samples were collected and their toxicity evaluated to aquatic species in a previous study in the agriculturally dominated Central Valley of California, United States. Pyrethroid insecticides were the main contributors to the observed toxicity. However, mortality in approximately one third of the toxic samples could not be explained solely by the presence of pyrethroids in the matrices. Hundreds of pesticides are currently used in the Central Valley of California, but only a few dozen are analyzed in standard environmental monitoring. A significant amount of unexplained sediment toxicity may be due to pesticides that are in widespread use that but have not been routinely monitored in the environment, and even if some of them were, the concentrations harmful to aquatic organisms are unknown. In this study, toxicity thresholds for nine sediment-associated pesticides including abamectin, diazinon, dicofol, fenpropathrin, indoxacarb, methyl parathion, oxyfluorfen, propargite, and pyraclostrobin were established for two aquatic species, the midge Chironomus dilutus and the amphipod Hyalella azteca. For midges, the median lethal concentration (LC₅₀) of the pesticides ranged from 0.18 to 964 μg/g organic carbon (OC), with abamectin being the most toxic and propargite being the least toxic pesticide. A sublethal growth endpoint using average individual ash-free dry mass was also measured for the midges. The no–observable effect concentration values for growth ranged from 0.10 to 633 μg/g OC for the nine pesticides. For the amphipods, fenpropathrin was the most toxic, with an LC₅₀ of 1–2 μg/g OC. Abamectin, diazinon, and methyl parathion were all moderately toxic (LC₅₀s 2.8–26 μg/g OC). Dicofol, indoxacarb, oxyfluorfen, propargite, and pyraclostrobin were all relatively nontoxic, with LC₅₀s greater than the highest concentrations tested. The toxicity information collected in the present study will be helpful in decreasing the frequency of unexplained sediment toxicity in agricultural waterways.     

Lung cancer and<Emphasis Type="Italic">CYP1A1</Emphasis> or<Emphasis Type="Italic">GSTM1</Emphasis> polymorphisms

Most chemical carcinogens are metabolized and activated in vivo by phase I enzymes including the microsomal cytochromes P450 and epoxide hydroxylases. The carcinogens and their metabolites are detoxified by phase II enzymes that in clude various transferases such as glutathion-S-transferases (GST). Increasing numbers of studies have demonstrated the association of the polymorphisms inGSTM1 (a member of GST) andCYP1A1 genes with the susceptibility to lung cancer. Subsequently, the polymorphisms appear to be important biomarkers that provide information for assessment of exposure and total burden of environmental carcinogens. Therefore, the investigation of the polymorphisms in these genes will provide information not only for the prediction of individual cancer risk but also for the prevention of cancer. In this review, we will summarize the polymorphisms in theGSTM1 andCYP1A1 genes and their relation to lung cancer susceptibility.     

<Emphasis Type="ItalicSmallCaps">HEALTH</Emphasis><Emphasis Type="Italic">GeoJunction</Emphasis>: place-time-concept browsing of health publications

Background  

The volume of health science publications is escalating rapidly. Thus, keeping up with developments is becoming harder as is the task of finding important cross-domain connections. When geographic location is a relevant component of research reported in publications, these tasks are more difficult because standard search and indexing facilities have limited or no ability to identify geographic foci in documents. This paper introduces HEALTH GeoJunction, a web application that supports researchers in the task of quickly finding scientific publications that are relevant geographically and temporally as well as thematically.     

Impact of <Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>-Dimethylformamide from Domestic Effluents on River Waters

The impacts of N,N-dimethylformamide (DMF) from domestic effluents on rivers were evaluated. The hourly DMF concentrations in the inflows (0.21–0.52 μg/L in mean) and the outflows (0.18–0.62 μg/L in mean) of two sewage treatment plants did not show any characteristic variations, and DMF was not removed at both plants. The monthly variations of DMF in the outflows of four sewage treatment plants (0.16–0.62 μg/L in mean) and three rivers (0.06–0.11 μg/L in mean) into which the outflows of the plants were discharged did not show any significant variations. The domestic DMF load per person was calculated to be 0.25 mg/d/person. The percent DMF loads of domestic effluents in the rivers were estimated to be below (8%–32%).     

Antibiotics for the treatment of Cholera, <Emphasis Type="Italic">Shigella</Emphasis> and <Emphasis Type="Italic">Cryptosporidium</Emphasis>in children

Background

Diarrhea is a major contributor to the burden of morbidity and mortality in children; it accounts for a median of 11% of all deaths among children aged less than 5 years, amounting to approximately 0.8 million deaths per year. Currently there is a dearth of literature exploring the effectiveness of antibiotics for diarrhea due to Cholera, Shigella and cryptosporidiosis in children.

Methods

We reviewed the literature reporting the effect of antibiotics for the treatment of diarrhea due to Cholera, Shigella and Cryptosporidium in children under five years. We used a standardized abstraction and grading format and performed meta-analyses to determine the effect of the treatment with various antibiotics on mortality and rates of clinical and bacteriological/parasitological failure. The CHERG Standard Rules were applied to determine the final effect of treatment with antibiotics on diarrhea morbidity and mortality.

Results

For Cholera; the evidence was weak to recommend any effect on mortality. For Shigella; there was no data on mortality; either all-cause or cause specific, hence we used clinical failure rates as a proxy for Shigella deaths and propose that treatment of Shigella dysentery with antibiotics can result in a 82% reduction in diarrhea mortality due to Shigella. For cryptosporidiosis; there was data on all-cause mortality but the evidence was weak hence we used clinical failure rates as a proxy for mortality to estimate that antimicrobial treatment of diarrhea due to cryptosporidiosis can result in a 54% reduction in mortality.

Conclusions

There is evidence to recommend antibiotic use for reduction of morbidity and mortality due to Cholera, Shigella and Cryptosporidium. We recommend that more clinical trials should be conducted to evaluate the efficacy and safety of first- and second- line drugs currently in use for treatment for diarrhea and dysentery in both developing and developed countries.

     

Effluent Toxicity Test Using Developmental Stages of the Marine Polychaete <Emphasis Type="Italic">Hydroides </Emphasis><Emphasis Type="Italic">elegans</Emphasis>

The US Environmental Protection Agency (USEPA) has established a suite of methods that use coastal invertebrate species as bioassay organisms to test industrial and domestic effluent as well as coastal waters for potential toxicity. Although these methods are used globally, the potential of such toxicity tests has not been adequately explored for Asian coastal waters. This study describes bioassay utilizing the gametes of Hydroides elegans to monitor coastal water quality and is based on the sensitivity of H. elegans embryo and larva to different concentrations of effluents and water samples collected from different regions of east coast of India. Among the water samples collected from different regions, seawater from Ennore station showed decrease in percentage of development, and 25% effluent concentration led to development arrest of H. elegans embryos. The different morphological effects produced by effluents clearly reflect the defect in early differentiation of embryonic cells. Since fertilization can be inhibited in the presence of any xenobiotic, both fertilization and early development can be used as a biological indicator for a rapid bioassay to monitor pollution. Toxicity tests utilizing early life stages of H. elegans are suitable for the assessment of effects produced by low levels of pollutants due to their high sensitivity to various contaminants relative to other marine species and also due to the relative simplicity of the bioassay.     

Fluid intake in urban China: results of the 2016 <Emphasis Type="Italic">Liq.In</Emphasis><Superscript><Emphasis Type="Italic">7</Emphasis></Superscript> national cross-sectional surveys

Purpose

To describe total fluid intake (TFI) and types of fluid consumed in urban China by age, gender, regions and city socioeconomic status relative to the adequate intakes (AI) set by the Chinese Nutrition Society.

Methods

In 2016, participants aged 4–9, 10–17 and 18–55 years were recruited via a door-to-door approach in 27 cities in China. In total, 2233 participants were included. The volumes and sources of TFI were collected using the Liq.In ⁷ record, assisted by a photographic booklet of standard fluid containers.

Results

The mean daily TFI among children, adolescents and adults were 966, 1177 and 1387 mL, respectively. In each age group, TFI was significantly higher in male vs female (981 vs 949, 1240 vs 1113, 1442 vs 1332; mL). Approximately 45, 36 and 28% of children, adolescents and adults reached the AI. Although plain water was the highest contributor to TFI, the contribution of sugar sweetened beverages (SSB) was ranked in the top three together with water and milk and derivatives. Approximately 27, 48 and 47% of children, adolescents and adults consumed more than one serving of SSB per day, respectively.

Conclusions

A relatively large proportion of participants did not drink enough to meet the AI in urban China. Many children, adolescents and adults consumed more than one serving of SSB per day. A majority of children, adolescents and adults in the study population do not meet both quantitative and qualitative fluid intake requirements, and signal socioeconomic disparities.

     

Effects of <Emphasis Type="Italic">trans</Emphasis>-10,<Emphasis Type="Italic">cis</Emphasis>-12 conjugated linoleic acid on cholesterol metabolism in hypercholesterolaemic hamsters

Background Conjugated linoleic acid (CLA) has received great attention in recent years because of its pleiotropic biological activities, but considerably fewer studies have been published addressing its role in serum lipids and atherosclerosis compared to other topics covered. Aims of the study The aim of the present study was to assess the effects of the trans-10,cis-12 isomer of CLA on cholesterolaemia and on several metabolic pathways involved in cholesterol metabolism in hamsters. Methods Animals were fed atherogenic diets supplemented with 0.5% linoleic acid, 0.5% trans-10,cis-12 CLA or 1.0% trans-10,cis-12 CLA, for 6 weeks. Serum lipoproteins were separated by FPLC. Cholesterol in serum and liver, as well as triacylglycerols and phospholipids in liver were assessed by spectrophotometry. 3-Hydroxy-3-methylglutaryl coenzyme A reductase (HMGCoAR), acyl-coenzyme A:cholesterol acyltransferase (ACAT) and cholesteryl ester hydrolase (CEH) activities were measured by radiometry, and LDL receptors were determined by Western blot. Results trans-10,cis-12 CLA feeding did not modify food intake nor final body weight. Although serum total cholesterol remained unchanged, when cholesterol fractions were analyzed a significant decrease in VLDL-cholesterol was observed in CLA-fed animals, without changes in HDL-cholesterol or LDL-cholesterol. trans-10,cis-12 CLA decreased cholesterol ester content and increased free cholesterol in liver. The activity of HMGCoAR was not modified. In contrast, ACAT activity was reduced by both CLA doses and CEH was increased by the high CLA dose. LDL receptors were significantly reduced by trans-10,cis-12 feeding when expressed as arbitrary units per mg of protein, however, the total receptor mass remained unchanged. Conclusions These results suggest that, under the present experimental conditions, trans-10,cis-12 CLA feeding reduces cholesterol esterification in liver and decreases the minority serum VLDL-cholesterol fraction, but it does not show a hypocholesterolaemic effect. A dose–response effect was not observed.     

Primary DNA damage and genetic polymorphisms for <Emphasis Type="Italic">CYP1A1</Emphasis>, <Emphasis Type="Italic">EPHX</Emphasis> and <Emphasis Type="Italic">GSTM1</Emphasis> in workers at a graphite electrode manufacturing plant

Background  

The results of a cross-sectional study aimed to evaluate whether genetic polymorphisms (biomarkers of susceptibility) for CYP1A1, EPHX and GSTM1 genes that affect polycyclic aromatic hydrocarbons (PAH) activation and detoxification might influence the extent of primary DNA damage (biomarker of biologically effective dose) in PAH exposed workers are presented. PAH-exposure of the study populations was assessed by determining the concentration of 1-hydroxypyrene (1OHP) in urine samples (biomarker of exposure dose).