Determination of 24 sulfonamide antibiotics in instant pastries by modified QuEChERS coupled with ultra performance liquid chromatography-tandem mass spectrometry.

There were few reports about antibiotic residues in egg-containing products. In the study, an effective method for the simultaneous determination of 24 sulfonamide antibiotics in two instant pastries based on a modified QuEChERS sample preparation technique coupled with ultra performance liquid chromatography-tandem mass spectrometry was developed. The results show that the average recoveries of the SAs at 5, 10, and 50 µg kg-1 levels were 67.6%-103.8%, with relative standard deviations (RSD) of 0.80-9.23%. The limit of detections (LODs) and limit of quantitations (LOQs) were 0.01-0.14 µg kg-1 and 0.02-0.45 µg kg-1, respectively. This method was suitable for analysis of 24 SAs in instant pastries.

Associations of urinary dichloroacetic acid and trichloroacetic acid exposure with platelet indices: Exploring the mediating role of blood pressure in the general population.

Human exposure to drinking water disinfection by-products (DBPs) is potentially linked to high blood pressure (BP), which may be associated with abnormal platelet activation. This study investigated whether the relationship between DBP exposure with platelet change was mediated by BP. DBP biomarkers, such as urinary dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA), BP and platelet indices from 505 adults from a hospital in Shijiazhuang, China were measured. The cross-sectional associations among DCAA and TCAA exposure, BP and platelet indices were explored through multivariable linear regressions, and the mediation effect of BP was evaluated using the Sobel-Goodman test. We observed that DCAA and TCAA were positively associated with systolic BP (all p for trends < 0.01), which was positively associated with platelet count (PLC) (p for trend < 0.05). Mediation analysis indicated that systolic BP fully mediated the associations of DCAA and TCAA with PLC. When BP was controlled, a previously inverse significant relation between DCAA and platelet distribution width (PDW) remained significant (p < 0.05). Obtained results suggested that exposure to DCAA may contribute to decreased PDW in humans. Systolic BP is a possible mediator of the association between DCAA exposure and PLC. TCAA may indirectly positively affect PLC by increasing systolic BP.

Urinary trichloroacetic acid and high blood pressure: A cross-sectional study of general adults in Shijiazhuang, China.

Exposure to trichloroacetic acid (TCAA) and its parent chemicals potentially linked to cardiovascular disease. However, the association between TCAA and blood pressure (BP) has not been studied to date. The purpose of this study was to examine the potential association between urinary TCAA levels and BP in a Chinese population. We measured BP parameters (including systolic BP, diastolic BP and pulse pressure) and TCAA concentrations in the urine of 569 adults from a primary health care clinic in Shijiazhuang, China. Logistic and linear regressions were used to investigate the relationships between the urinary TCAA levels and BP parameters. To evaluate the robustness of the results, we conducted sensitivity analyses by re-analysing data after excluding urine samples with extreme specific creatinine values. We found that urine TCAA levels were positively associated with systolic BP and pulse pressure based on trend tests after adjusting for potential confounders (both p for trend < 0.05). Finally, only the association of TCAA with systolic BP remained significant in the sensitivity analyses (p < 0.05). Our results suggested that TCAA exposure was associated with increased BP in adults. Because urinary TCAA has been proposed as a valid biomarker of disinfection by-product (DBP) ingestion through disinfected drinking water, our results further suggest that exposure to drinking water DBPs may contribute to high BP in humans. Additional research is needed to confirm these findings and to evaluate opportunities for intervention.

Phthalates in residential and agricultural soils from an electronic waste-polluted region in South China: distribution, compositional profile and sources.

Electronic waste (e-waste) recycling has proven to be a significant source of phthalate (PAE) contamination in the environment. A detailed investigation was conducted to understand the concentration, distribution, profile and possible source of PAEs in residential and agricultural soils from Guiyu, Shantou, China, the largest e-waste processing and recycling areas in the world. Sixteen PAEs were analysed in 46 surface soil samples from three different sampling areas in terms of individual and total concentrations, together with pH and soil organic matter. High concentrations of the total PAEs were found in residential area A (more than 20,000 ng g-1), revealing a clear urban pulse, whereas in residential area B and agricultural areas, concentrations were lower than 10,000 ng g-1. The dominant PAEs were bis (2-nbutoxyethyl) phthalate, bis (4-methyl-2-pentyl) phthalate and dicyclohexyl phthalate. These PAEs were high-molecular weight PAEs (alkyl chains ≥ 6 carbons) and mainly derived from polyvinyl chloride commonly used in electrical and electronic equipment, indicating a distinctive composition in relation to the e-waste area. Three individual and the total PAEs exhibited significant positive correlations with pH. Principal component analysis indicated that PAEs were mainly distributed in three groups according to the alkyl chain length and potential source. This study showed that the informal e-waste recycling has already introduced PAEs into surrounding areas as a pollutant which should draw more attention and regulatory control.