Sediment cores from 12 Chinese lakes were analyzed to investigate the historical inputs of polybrominated diphenyl ethers (PBDEs) and decabromodiphenylethane (DBDPE) during the past few decades. Concentrations of ΣPBDE₁ (sum of tri- to hepta-BDEs), ΣPBDE₂ (sum of nona- to deca-BDEs) and DBDPE in the surface sediments were 0.02–0.29 ng g⁻¹, 0.46–46.6 ng g⁻¹ and 1.02–3.64 ng g⁻¹, respectively. The temporal trends of PBDEs and DBDPE followed a general increase from the bottom to the surface. The calculated fluxes for ΣPBDE₁, ΣPBDE₂ and DBDPE were 0.001–0.09, 0.03–4.24, and 0.05–0.31 ng cm⁻² yr⁻¹, and the inventories were 0.09–7.86, 0.91–461, and 3.83–24.6 ng cm⁻², respectively. The urbanization and industrialization are highly related to the contamination of PBDEs and DBDPE in sediments. The DBDPE input in recent years was still lower than ΣPBDE₂ but the temporal trends indicated that the contamination would increase with the increasing usage of DBDPE in the future.

This study provides a combined dataset on N loss pathways and fluxes from sloping cropland in the purple soil area, southwestern China. A lysimeter experiment was conducted to quantify nitrate leaching (May 2004–May 2010) and N₂O emission (May 2009–May 2010) losses. Nitrate leaching was the dominant N loss pathway and annual leaching fluxes ranged from 19.2 to 53.4 kg N ha⁻¹, with significant differences between individual observation years (P < 0.05). Direct N₂O emissions due to N fertilizer use were 1.72 ± 0.34 kg N ha⁻¹ yr⁻¹, which corresponds to an emission factor of 0.58 ± 0.12%. However, indirect N₂O emissions caused by nitrate leaching and surface runoff N losses, may contribute another 0.15–0.42 kg N ha⁻¹ yr⁻¹. Our study shows that nitrate leaching lowered direct N₂O emissions, highlighting the importance for a better understanding of the tradeoff between direct and indirect N₂O emissions for the development of meaningful N₂O emission strategies.

Available data were reviewed to assess the status of contamination by persistent organic pollutants (POPs), including organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs), perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA), in drinking water sources and coastal waters of China. The levels of POPs in China's waters were generally at the high end of the global range. A comparison of China's regulatory limits indicated that PCBs in rivers and coastal water may pose potential human health risk. Occurrence of DDTs in some rivers of China may also pose health risk to humans using the regulatory limits of DDTs recommended by the European Union. Future monitoring of POPs in China's waters should be directed towards analytes of concern (e.g. PCBs and PCDD/Fs) and to fill data gaps for analytes (e.g. PBDEs, PCDD/Fs, and chlordane) and in watersheds/regions (e.g. West China) where data are scarce.

There are limited data on persistent organic pollutants (POPs) in the soils of the Tibetan Plateau. This paper presents data from a survey of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in 40 background surface (0–5 cm) soils of the Tibetan Plateau. Soil concentrations (pg/g, dw) ranged as follows: DDTs, 13-7700; HCHs, 64-847; HCB, 24-564; sum of 15 PCBs, 75-1021; and sum of 9 PBDEs, below detection limit −27. Soil DDT, HCB, PCB and PBDE concentrations were strongly influenced by soil organic carbon content. HCH concentrations were clearly associated with the proximity to source regions in south Asia. The air–soil equilibrium status of POPs suggested the Tibetan soils may be partial “secondary sources” of HCB, low molecular weight PCBs and HCHs and will likely continue to be “sinks” for the less volatile DDE and DDT.

China's economy has grown significantly and concomitantly so has the demand for home and personal care (HPC) products. The detection of chemicals used in HPC products is increasing in profile as China strives to improve its environmental management. China is developing robust exposure models for use in regulatory risk-based assessments of chemicals, including those chemicals used in HPC products. Accurate estimates of chemical emissions play an important role within this. A methodology is presented to derive spatially refined emissions from demographic and economic indicators with large variations in emissions calculated, showing product usage being higher in East and South China. The less affordable a product, the greater the influence per capita Gross Domestic Product has on the product distribution. Lastly, more spatially resolved input data highlights greater variation of product use. Linking product sales data with population density increased the observed variability in absolute usage distribution of HPC products at the county > province > regional > country scale.

Hexabromocyclododecanes (HBCDs) have been considered candidate persistent organic pollutants, however, environmental data on their presence in China, a major world market, are limited. In this study, airborne particle-bound HBCDs in Shanghai, China were quantified with liquid chromatography–tandem mass spectrometry, and their total concentrations varied from 3.21 to 123 pg/m³. The industrial area showed about three times higher HBCD levels than the urban areas. Gamma-HBCD dominated in particle-associated HBCDs in the industrial area, while α-HBCD was the major diastereomer of the urban areas, which is quite different from the pattern of technical products. Besides α-, β- and γ-HBCDs, δ-HBCD was also detected in all samples (0.09–6.31 pg/m³), while no ɛ-HBCD was found. Airborne β- and γ-HBCDs were racemic in most studied areas due to their chiral signatures showing no significant difference from commercial mixture. Fractions of (+)-α-HBCD (0.417–0.467), however, suggested the enrichment of (−)-α-HBCD and the involvement of enantioselective bioprocesses.

High levels of polybrominated diphenyl ethers (PBDEs) have been extensively reported in urban areas and at e-waste recycling sites in coastal China. However, data are scarce in northern China and are not available in rural areas at all. In addition, it is often believed that air concentrations in rural areas are lower than those in urban areas without distinguishing rural residential areas and open fields. In this study, air samples were collected at 17 sites covering urban and rural (residential and open field) areas in northern China using active samplers. With BDE-209 dominated in all congeners, the average concentrations of BDE-209 (41 ± 72 pg/m³) and other 13 PBDEs (16 ± 12 pg/m³) were significantly lower than those found in south China, such as in Guangzhou or Hong Kong. On average, the total PBDE concentrations at the urban sites were 2.2 and 2.9 times of those at the rural residential and field sites, respectively.

Stomatal ozone flux and flux–response relationships were derived for winter wheat (Triticum aestivum L.) grown under fully open-air ozone fumigation. A stomatal conductance (gₛₜₒ) model developed for wheat in Europe was re-parameterized. Compared to European model parameterizations, the main changes were that the VPD and radiation response functions were made less and more restrictive, respectively, and that the temperature function was omitted. The re-parameterized gₛₜₒ model performed well with an r² value of 0.76. The slope and intercept of the regression between observed and predicted gₛₜₒ were not significantly different from 1 to 0, respectively. An ozone uptake threshold of 12 nmol m⁻² s⁻¹ was judged most reasonable for the wheat flux–response relationship in subtropical China. Judging from both flux- and concentration-based relationships, the cultivars investigated seem to be more sensitive to ozone than European cultivars. The new flux–response relationship can be applied to ozone risk assessment in subtropical regions.

We investigated occurrence of selected compounds (4-t-octylphenol: 4-t-OP; 4-nonylphenols: 4-NP; bisphenol-A: BPA; estrone: E1; 17β-estradiol: E2; triclosan: TCS) and estrogenicity in surface water and sediment of the Yellow River in China by using combined chemical analysis and in vitro yeast screen bioassay. Estrogenic compounds 4-t-OP, 4-NP, BPA, E1, E2 and TCS were measured in the water samples, with their average concentrations of 4.7, 577.9, 46.7, 1.3, ND and 6.8 ng/L, respectively. In sediment, the average concentrations of 4-t-OP, 4-NP, BPA and TCS were 35.7, 0.5, 1.7 and 0.7 ng/g while E1 and E2 were not detected in the sediments of all selected sites. In general, the estrogenic compounds in surface water and sediment of the Yellow River were at relatively low levels, thus having medium to minimal estrogenic risks in most sites except for the site of east Lanzhou with high estrogenic risks.

To investigate the bioaccumulation patterns of microcystins (MCs) in organs of two gastropods, samples were collected in Lake Dianchi monthly from May to October, 2008, when cyanobacteria typically bloom. The average MCs concentrations for Radix swinhoei (pulmonate) and Margarya melanioides (prosobranch) tended to be similar for the different organs: the highest values in the hepatopancreas (9.33 by 3.74μg/g DW), followed by digestive tracts (1.66 by 3.03μg/g DW), gonads (0.45 by 1.34μg/g DW) and muscles (0.22 by 0.40μg/g DW). Pulmonate had higher value than prosobranch because of the stronger bioaccumulation ability in hepatopancreas. The levels in organs of R. swinhoei were correlated with environmentally dissolved MCs, but influenced by intracellular MCs for M. melanioides. The estimated MCs concentrations in edible parts of M. melanioides were beyond the WHO’s provisional tolerable daily intake (0.04μg/kg), suggesting the risk of consumption of M. melanioides from the lake.