Occurrence of polycyclic aromatic hydrocarbons in water and sediment samples from KwaZulu Natal Province,South Africa

Solid‐phase extraction (SPE) and ultrasonic extraction (UE) techniques followed by Gas Chromatography‐Mass Spectrometry (GC‐MS) have been modified for qualitative and quantitative analysis of polycyclic aromatic hydrocarbons (PAHs) in water and sediment samples. Percentage recoveries of PAHs ranged from 85 to 121% in water and 82 to 117% in sediment samples. The limits of detection (LOD) and limits of quantification (LOQ) ranged from 0.02 to 0.2 and 0.05 to 0.5 µg/L for SPE while for UE, they were between 0.008–0.09 and 0.02–0.30 µg/kg, respectively. The concentration levels of PAHs (naphthalene, acenaphthene, acenaphthylene, fluorine, anthracene, phenanthrene and pyrene) detected in water samples were 0.071–2.7, 2.0–10.4 and 2.5–3.5 µg/L in wastewater, river water, and dam water, respectively. In sediment samples, concentration levels of PAHs were between 2.8–42.0 and 2.8–3.9 µg/kg, in river and dam sediment, respectively.     

The reactions of chlorine dioxide with aquatic organic materials and their health effects

This review describes the main reactions that have been studied in water between chlorine dioxide and various groups of organic compounds. Although the reactions of ClO₂ with some model organic compounds have also been summarised, special emphasis has been given to the reaction products that were found in actual water plants treated with ClO₂ or under conditions closely related to these.Some conclusions were drawn with respect to the mechanism by which ClO₂ reacts with aquatic organic materials. As a result of the proposed reaction mechanisms a prediction was made as to which main organic products will be formed and which health effects may be expected.The last section of the review deals with the impact of ClO₂ on some kinds of organic micropollutants, such as pesticides and polycyclic aromatic hydrocarbons (PAH) which are often found in surface water sources and thus may also be found in drinking water.     

Disinfection of advanced wastewater treatment effluent by chlorine, chlorine dioxide and ozone: Experiments using seeded poliovirus

Chlorine, chlorine dioxide and ozone were tested as chemical disinfectants against seeded poliovirus and naturally-occurring fecal coliform organisms in wastewater effluent that had received secondary treatment followed by bench scale advanced wastewater treatment (AWT). The AWT sequence consisted of chemical treatment with lime or alum followed by mixed media filtration. The resulting effluent had low suspended solids concentrations but chemical oxygen demand and nitrogen concentrations only slightly lower than those of secondary effluent. Lime treatment produced greater reductions than alum treatment in virus numbers, but not in fecal coliform organisms.

With both chlorine and chlorine dioxide, in order to reduce seeded poliovirus to less than detectable levels, it was necessary to use doses comparable to those required to disinfect secondary effluent. The required contact times of 30–60 min were also comparable. Utilized ozone doses of 2–4 mg l⁻¹ were required to reduce seeded poliovirus to less than detectable levels in AWT effluent. Naturally-occurring fecal coliform organisms were unaffected at these ozone doses, but were inactivated at higher doses. Because they were more resistant than seeded poliovirus to ozone, fecal coliform organisms show promise as indicators for ozone disinfection.     

次氯酸钠、二氧化氯处理水厂排泥水试验研究

以南方地区某水厂排泥水为处理对象,分别用次氯酸钠、二氧化氯进行了小试。结果表明,次氯酸钠、二氧化氯对排泥水中的细菌、藻类有一定的去除效果,达到同期原水水平,但对水中剑水蚤的灭活效果不显著;同时,水中UV254出现明显的上升。     

Reproductive hormones in relation to polycyclic aromatic hydrocarbon (PAH) metabolites among non-occupational exposure of males

A limited number of studies have suggested that exposure to PAHs may affect reproductive hormones. Subjects (n = 642) in this study were from the affiliated hospitals of Nanjing Medical University. Individual exposures to PAHs were measured as spot urinary concentrations of four PAH metabolites, including 1-naphthol (1-N), 2-naphthol (2-N), 2-hydroxyfluorene (2-OF) and 1-hydroxypyrene (1-OP), which were adjusted by urinary creatinine (CR). Blood samples were collected to measure serum levels of reproductive hormones, including follicle-stimulating hormone (FSH), luteotrophic hormone (LH), estradiol (E2), testosterone (T) and prolactin (PRL). All of the subjects had detectable levels of the four metabolites of PAHs in their urine samples. The median concentrations of 1-N, 2-N, 2-OF and 1-OP were 2.440, 4.176, 2.843 and 1.148 µg/g of CR. There were significant P-values between increased CR-adjusted 1-N tertiles and E2 concentration, 2-OF tertiles and LH, FSH level, 1-OP and E2 level. The multivariate linear regression results also showed significant correlation between the levels of serum LH and 1-OP (the adjusting P-value was 0.048), but no correlations were found between other hormones and the level of PAH metabolites. These observed correlations between levels of hydroxy-PAH and some altered hormones indicated slight endocrine effects on adult men with PAH exposure.     

再生水紫外-氯组合消毒与单一氯消毒比较分析

利用准平行光束仪对再生水进行了紫外灭活大肠杆茵试验,并考察了紫外-氯组合消毒与单一氯消毒的消毒效果.结果表明,与单一氯消毒相比,紫外-氯组合消毒可有效降低氯的投加量.在组合消毒试验条件下,大肠杆菌完全灭活,紫外剂量从3mJ/cm2提高到5mJ/cm2,加氯量可降低1mg/L;灭活率相同条件下,紫外剂量与加氯量的关系符合...     

Liquid/suspended solid phase partitioning of polycyclic aromatic hydrocarbons in coal coking wastewaters

Wastewater samples were collected from five streams among two coke plants and characterized by high pressure liquid chromatography and gas chromatographic mass spectrometry. Wastewater streams included the ammonia still influent, ammonia still effluent and biological oxidation effluent. Samples collected from these streams were separated into liquid and suspended solid phases and each phase was analyzed for eleven polycyclic aromatic hydrocarbons (PAH). Total wastewater concentrations for these compounds ranged from about 2000 μg l⁻¹ in the ammonia still influent to 5–120 μg l⁻¹ in the biological oxidation effluent. Wastewater PAH were partitioned between liquid and suspended solid phases, and in most samples suspended solid phase PAH accounted for approx. 80% or more of total wastewater PAH. Partitioning in the biological oxidation effluent stream was correlated with aqueous solubility and n-octanol/water partition coefficients. Wastewater treatment consisting of sedimentation, ammonia stripping, and biological oxidation generally reduced liquid phase PAH concentrations to the range of 1 μg l⁻¹ or less. Effective removal of wastewater suspended solids will reduce total effluent PAH concentrations, hence there is need to address issues regarding removal of residual wastewater suspended material including characterization of the distribution of PAH with respect to suspended particle size.     

Ozonation of polycyclic aromatic hydrocarbons in oil/water-emulsions: mass transfer and reaction kinetics

The ozonation of highly condensed polycyclic aromatic hydrocarbons (PAH) was studied in oil/water-emulsions, which are comparable to poorly water-soluble PAH in industrial wastewaters and at contaminated sites. As there was a lack of knowledge about the ozonation in oil/water-emulsions, first the ozone mass transfer was studied and optimized from the gas to the water phase and from the water to the oil phase. The ratio of mass transfer and oxidation reaction was determined by the Hatta-number and revealed a slow, quasi homogeneous reaction of ozone with PAH inside the oil droplets. Because the ozone gas concentration had no influence under the optimized conditions, the selective PAH-ozonation could be described microkinetically by a direct ozone reaction of pseudo-first order regarding PAH-concentrations. The determined PAH mean reaction rate constants of 1.02 min(-1) in oil/water-emulsions are in the upper range as found for PAH dissolved in water. These results give a new insight into the ozonation in the three-phase systems and into the treatment of highly condensed, hardly biodegradable PAH.     

Application of multi-way models to the time-resolved fluorescence of polycyclic aromatic hydrocarbons mixtures in water

The time-resolved laser-induced fluorescence of a series of polycyclic aromatic compounds (PAHs) and mixtures of these latter in aqueous solution was measured by means of an apparatus equipped with optical fibers, which allows their real time in situ monitoring. The potential of such spectroscopic technique, yielding 4-way fluorescence data arrays, together with the application of multi-way models to the matricized data, was tested for the resolution of complex aqueous mixtures containing low concentrations of PAHs, as typical fluorescent pollutants in aquatic systems. PARAllel FACtors analysis was employed for the qualitative resolution of PAHs mixtures and for calculating the fluorescence lifetimes of single PAHs; n-way partial least squares analysis was applied for evaluating the concentration of the single PAHs in the aqueous mixtures.     

Distributions of polycyclic aromatic hydrocarbons in surface waters, sediments and soils of Hangzhou City, China

Ten polycyclic aromatic hydrocarbons (PAHs) were simultaneously measured in 17 surface water samples and 11 sediments of four water bodies, and 3 soils near the water-body bank in Hangzhou, China in December 2002. It was observed that the sum of PAHs concentrations ranged from 0.989 to 9.663 microg/L in surface waters, from 132.7 to 7343 ng/g dry weight in sediments, and from 59.71 to 615.8 ng/g dry weight in soils. The composition pattern of PAHs by ring size in water, sediment and soil were surveyed. Three-ring PAHs were dominated in surface waters and soils, meanwhile sediments were mostly dominated by four-ring PAHs. Furthermore, PAHs apparent distribution coefficients (K(d)) and solid f(oc)-normalized K(d) (e.g. K(oc)= K(d) / f(oc)) were calculated. The relationship between logK(oc) and logK(ow) of PAHs for field data on sediments and predicted values were compared. The sources of PAHs in different water bodies were evaluated by comparison of K (oc) values in sediments of the river downstream with that in soils. Hangzhou section of the Great Canal was heavily polluted by PAHs released from industrial wastewater in the past and now PAHs in sediment may serve as sources of PAHs in surface water. PAHs in Qiantang River were contributed from soil runoff. Municipal road runoff was mostly contributed to West Lake PAHs.     

Atmospheric deposition of polycyclic aromatic hydrocarbons (PAHs) in mosses (Hypnum cupressiforme) in Hungary

The atmospheric deposition of polycyclic aromatic hydrocarbons (PAHs) was investigated in Hungary by analyzing a moss (Hypnum cupressiforme) species as a bioindicator. In the autumn of 1997, samples were collected at 29 sites distributed across Hungary. The concentrations of total PAH at these sites were in the range of 0.1567-10.45 x 10(4) microg kg(-1) with a mean value of 1.87 x 10(4) microg kg(-1). More than 99% of the total PAHs atmospheric deposition were low molecular weight PAHs (up to 3 ring compounds). The total PAH values showed no correlation with metal concentrations. However, most of the sites in this region showed a positive linear relationship between PAHs levels and traffic volume (r2 = 0.83; P < 0.001) while no relationship existed between PAH levels and population (r2 = 0.01; P > 0.1). Atmospheric deposition of PAHs at different regions in Hungary may be due to incomplete combustion of fuel. The total concentrations of PAHs were compared to the PAH levels in vegetation samples collected from different regions around the world. The highest PAHs concentrations accumulated were found in Hypnum cupressiforme than other vegetation species. A greater affinity for PAH compounds by Hypnum cupressiforme than other moss species probably caused larger amounts of accumulation. A relationship between accumulations of PAH compounds in Hypnum cupressiforme and octanol-air partition coefficients was obtained and is briefly discussed.     

HPLC determination of polycyclic aromatic hydrocarbons (PAHs) in the littoral urban sewage area of cortiou (Marseille,France)

A selective method for determining polycyclic aromatic hydrocarbons (PAHs) in sediments using solid‐phase extraction and RP‐HPLC with fluorescence and UV detection is described. The complete analytical method is used to surface sediments from the creek of Cortiou (France). Sewage from the urban area of Marseille is delivered to the creek. PAH levels in sediments (µg/g) range between 2.251 µg/g (for the benzo(a)anthracene) and 相似文献   

二氧化氯/混凝剂工艺处理含铁水的试验研究

通过向含铁水中投加二氧化氯和混凝剂,考察了二氧化氯对水中铁的去除效果及其影响因素。结果表明,二氧化氯投加量、原水pH、预氧化时间和混凝剂投加量对铁的去除效果均有较大的影响。当原水Fe2+浓度为5 mg/L时,二氧化氯最佳投加量为5 mg/L,最佳氧化时间为10 min,混凝剂的最佳投加量为1 mg/L,最佳pH值为7～9,对铁离子的去除率可达到94.0%。     

Studying associations between urinary metabolites of polycyclic aromatic hydrocarbons (PAHs) and cardiovascular diseases in the United States

The association between background, enduring environmental exposure to polycyclic aromatic hydrocarbons (PAHs) and cardiovascular diseases has not been well studied in the general population. In this study, we used the National Health and Nutrition Examination Survey (NHANES) 2001-2004 to investigate the associations between eight monohydroxy PAHs (OH-PAHs) and self-report CVD. In a logistic regression model adjusting for cigarette smoking and other covariates, phenanthrene metabolite, 2-hydroxyphennathrene (2-PHEN), was significantly associated with self-report CVD. Compared to subjects within the lowest tertile of 2-PHEN, subjects within the middle and highest tertiles had higher self-report CVD (the 2nd tertile: AOR = 1.29, 95%CI: 0.97-1.72; the 3rd tertile: AOR = 1.45, 95%CI: 1.01-2.07; p for trend = 0.04). In addition, fluorene metabolite (i.e. 2-hydroxyfluorene) also showed a marginally significant linear trend with self-report CVD (p for trend = 0.07). Further studies are necessary to explore the associations between these highly prevalent pollutants and CVD.     

Health risk assessment on dietary exposure to polycyclic aromatic hydrocarbons (PAHs) in Taiyuan, China

Twenty-five kinds of seven categories of foods were sampled in December 2008 and the concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) were determined. The highest level of total PAHs was detected in pork (195.30 ng/g) whereas the lowest concentration was found in milk (8.73 ng/g). The median values of B[a]P equivalent (B[a]P_eq) daily exposure doses for children, adolescents, adults and seniors of male were estimated to be 392.42, 511.01, 571.56 and 532.56 ng/d, respectively, whereas those for the above population groups of female were found to be 355.16, 440.51, 487.64 and 444.85 ng/d, respectively. The incremental lifetime cancer risk (ILCR) values at the 22.1th, 26.1th, 12.7th, 24.9th, 22.7th, 27.0th, 12.9th, and 25.5th percentiles for male children, male adolescents, male adults, male seniors, female children, female adolescents, female adults and female seniors, respectively, were larger than 10^− 6, indicating high potential carcinogenic risk, and were larger than 10^− 4 at the 74.5th, 78.7th, 60.6th, 77.4th, 75.3th, 79.5th, 60.8th and 77.9th percentiles for the above groups, respectively, which implied significant cancer risk. Sensitivity analysis found that the two variables of oral cancer slope factor of benzo(a) pyrene (SF) and the daily dietary PAH exposure level (ED) had the greater impact than that of body weight (BW) on the ILCR.     

Household air pollution and personal exposure to nitrated and oxygenated polycyclic aromatics (PAHs) in rural households: Influence of household cooking energies

Residential solid fuels are widely consumed in rural China, contributing to severe household air pollution for many products of incomplete combustion, such as polycyclic aromatic hydrocarbons (PAHs) and their polar derivatives. In this study, concentrations of nitrated and oxygenated PAH derivatives (nPAHs and oPAHs) for household and personal air were measured and analyzed for influencing factors like smoking and cooking energy type. Concentrations of nPAHs and oPAHs in kitchens were higher than those in living rooms and in outdoor air. Exposure levels measured by personal samplers were lower than levels in indoor air, but higher than outdoor air levels. With increasing molecular weight, individual compounds tended to be more commonly partitioned to particulate matter (PM); moreover, higher molecular weight nPAHs and oPAHs were preferentially found in finer particles, suggesting a potential for increased health risks. Smoking behavior raised the concentrations of nPAHs and oPAHs in personal air significantly. People who cooked food also had higher personal exposures. Cooking and smoking have a significant interaction effect on personal exposure. Concentrations in kitchens and personal exposure to nPAHs and oPAHs for households using wood and peat were significantly higher than for those using electricity and liquid petroleum gas (LPG).     

Environmental exposure to polycyclic aromatic hydrocarbons,kitchen ventilation,fractional exhaled nitric oxide,and risk of diabetes among Chinese females

Diabetes is related to exposure to polycyclic aromatic hydrocarbons (PAHs), inflammation in the body, and housing characters. However, associations of urinary monohydroxy‐PAHs (OH‐PAHs) or fractional exhaled nitric oxide (FeNO) with diabetes risk in relation to housing characters are unclear. In this study, 2645 individuals were drawn from the baseline survey of the Wuhan‐Zhuhai Cohort Study. Associations of diabetes with urinary OH‐PAHs or FeNO among cooking participants were estimated using logistic regression models. Among women with self‐cooking meals, urinary OH‐PAH levels were positively associated with diabetes risk (P < .05); the cooking women with high FeNO (≥25 ppb) had a 59% increase in the risk of diabetes (OR: 1.59, 95% CI: 1.06, 2.38), compared with those with low FeNO (<25 ppb). The cooking women with use of kitchen exhaust fans/hoods had a 52% decrease in the risk of diabetes (OR: 0.48, 95% CI: 0.27, 0.84), compared with those with nonuse of kitchen exhaust fans/hoods. The results indicated that the cooking women had an elevated risk of diabetes, which may be partly explained by an increase in the PAH body burden and higher inflammatory responses. Use of kitchen exhaust fan/hood can be associated with a lower risk of diabetes.     

自由氯、氯胺和顺序氯化对饮用水消毒效果的试验研究

研究了自由氯、氯胺和顺序氯化三种消毒方式对大肠埃希氏菌和粪肠球菌的灭活效果.结果表明,自由氯浓度越高,对细菌的灭活速率和最终灭活率越大;氯胺浓度越高,对细菌的灭活速率和最终灭活率越大;顺序氯化消毒效果优于单独使用自由氯或氯胺时的消毒效果.同时,还探讨了pH和温度对三种消毒方式的影响.     

The residual dynamic of polycyclic aromatic hydrocarbons and organochlorine pesticides in fishponds of the Pearl River delta, South China

Hong Kong and South China are the most developed regions within China. The industrialization in these areas has resulted in severe environmental problems. Sediment and biotic samples including tilapia (Oreochromis mossambicus), bighead carp (Aristichthys nobilis), grass carp (Ctenopharyngodon idellus), crucian carp (Carassius auratus) and mandarin fish/fresh water grouper (Siniperca chuatsi) were collected from different fishponds in the Pearl River Delta (Tanzhou, Sanjiao, Guangzhou, Shipai, Changan and Mai Po) for the analysis of polycyclic aromatic hydrocarbons (PAHs) and organochlorine (OC) pesticides. Mandarin fish, which belongs to the highest trophic level, accumulated the highest concentrations of PAHs and DDTs among all fish species. The levels of DDTs in fish samples ranged from 1.5 to 62ng g-1 (wet wt.), with more than 30% of the fish samples exceeding the limit of 14.4ng g-1 (wet wt.) for human consumption recommended by US EPA (2000). Levels of PAHs in fish samples ranged from 1.91 to 224.03ng g-1 (wet wt.), but the potency-weighted total concentrations of PAHs in all muscle tissues were below the guideline value of 0.67ng g-1 (wet wt.) for human consumption set by US EPA (2000). The guideline value calculated was based on a tissue consumption rate of 142.2g day-1 (4-5 meals per week), which is a more protective rate for populations with a high consumption of fish, like Chinese and Asians. The effect of lipid content in PAHs and DDTs accumulation in fish tissue was not significant in general.