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1.
Twelve beaches on the northwestern Arabian Gulf coast of Kuwait were surveyed for the occurrence of plastic particles, tar balls and tar lumps. Particles were found on all beaches and were abundant on four: Suleibkhat, Fintas, Fahaheel and New Al Khiran. Most particles were composed of low-density polyethylene, but a few were of high-density polyethylene, polypropylene and polystyrene. Many were weathered and had traces of tar. Tar lumps and balls were present on all beaches, but were not as abundant as was expected, considering the heavy volume of oil tanker traffic in this region of the Arabian Gulf. Tar appeared to be less abundant than it was in 1979. With at least 33 plastics factories operating on the coast of Kuwait, it is possible that plastic particles occur more abundantly than has been observed in this study. The high winds and concurrent wave activity, which often vary in strength and direction but regularly occur here, probably play an important role in dispersing plastic particles which are washed up on to these beaches, making it difficult to accurately measure their abundance.  相似文献   

2.
The increasing production and use of plastic in the Arabian Gulf combined with shipping and waste disposal practices, have increased the concentration of plastic particles on the sea's surface and beaches. The objective of this investigation was to provide an assessment of the abundance, distribution, potential sources and significance of industrial plastic on the western beaches of the United Arab Emirates on the Arabian Gulf and on the eastern beaches on the Gulf of Oman. The abundance of stranded plastic pellets was highly uneven. By early 1992 alarming levels of fresh plastic pellets were noticed on the Arabian Gulf beaches of the UAE. Large numbers of 25 kg sacks of white plastic spherules manufactured by (SABIC) in Jubail, Saudi Arabia were washed ashore. When compared to the west coast on the Arabian Gulf, the east coast on the Gulf of Oman exhibited much lower levels of plastic pellets. When compared to other parts of the world, the beaches of the UAE on the Arabian Gulf are considered to be heavily polluted with industrial plastic.  相似文献   

3.
This study represents a forensic chemical analysis to define the liability for the coastal bitumens polluting the beaches of the Mediterranean city of Alexandria. Six tar balls collected from several locations along the coast of the city were analyzed for their acyclic and polycyclic hydrocarbons as well as sulfur heterocycles using GC/FID, GC/AED and gas chromatography/mass spectrometry techniques. The analysis of one Egyptian crude oil is also included as a possible source oil. The tar ball samples were at early stages of weathering. Based on the GC traces and biomarker signatures, the tar balls could be genetically different. One sample collected from the Eastern Harbor region appears to be a Bunker C type fuel produced from Egyptian crudes. The refining process has removed the low molecular weight components. On the other hand, the wide n-alkane distribution together with the absence of an unresolved complex mixture suggests that crude oils probably from tank washings, ballast discharges or accident spills from tankers could have contributed significantly to the other tar ball samples. The distribution of source specific hopane and sterane markers revealed that the tar samples probably originate from different oil fields.  相似文献   

4.
Whole samples of Palaemon elegans Rathke, 1837 and eggs of Paracentrotus lividus Lamarck, 1816 were collected on the coast of Ras Beirut, Lebanon in the summer and fall of 1977 and the spring of 1978. All were analysed for lead, cadmium, copper and other heavy metals. Lead concentrations in both the prawns and sea urchin eggs appeared to be highest in the summer and lowest in the spring, whereas cadmium was low in all seasons with only a few elevated readings. The strongest tendency towards seasonal variation was seen in the copper levels of the prawns, which were high in summer, much lower in fall, and then high again in spring. Results of the analyses for nickel, iron, zinc and chromium are also discussed. Of the various possible sources of heavy metals in the Ras Beirut coastal area, untreated sewage, pesticide residues, and automobile exhaust are the most important.  相似文献   

5.
结合目前铬渣解毒现状,提出生物质焦油热解还原铬渣的新技术,利用生物质气化副产物焦油作为解毒剂,进而提高铬渣解毒和资源化水平,降低能耗。将生物质焦油和铬渣混合制成球团通过热解实现Cr(VI)向Cr(III)的形态转化,对影响焦油热解还原铬渣的主要因素:温度、铬渣粒径、球团尺寸、铬渣与焦油当量比等进行探讨。结果表明:还原铬渣的质量随温度升高而提高,温度超过400℃后无明显变化,减小铬渣粒径与球团尺寸可明显提高还原质量。当热解温度为400℃,还原时间10 min,铬渣与焦油当量比2.29,铬渣粒径0.074 mm,球团粒径2.5 mm时,可得到Cr(VI)还原率98.65%的还原铬产品。  相似文献   

6.
Eriksson C  Burton H 《Ambio》2003,32(6):380-384
One hundred and sixty four plastic particles (mean length 4.1 mm) recovered from the scats of fur seals (Arctocephalus spp.) on Macquarie Island were examined. Electron micrographs of 41 of the plastic particles showed that none could be identified as plastic pellet feedstock from their shapes. Commonly, such pellets are cylindrical and spherical. Instead, all the 164 plastic particles from the seal scats were angular particles of 7 colors (feedstock particles are normally opaque or white) and could be classified into 2 categories: i) fragmented along crystal lines and likely to be the result of UV breakdown; and ii) worn by abrasion (where striations were clearly visible) into irregular shapes with rounded corners. White, brown, green, yellow and blue were the most common colors. In composition, they came from 5 polymer groups; polyethylene 93%, polypropylene 4%, poly(1-Cl-1-butenylene) polychloroprene 2%, melamine-urea (phenol) (formaldehyde) resin 0.5%, and cellulose (rope fiber) 0.5%. The larger groups are buoyant with a specific gravity less than that of seawater. These small plastic particles are formed from the breakdown of larger particles (fragments). Their origin seems to be from the breakdown of user plastics washed ashore and ground down on cobbled beaches. Certainly most particles (70%) had attained their final form by active abrasion. It is hypothesized that the plastic particles were washed out to sea and then selected by size and consumed by individuals of a pelagic fish species, Electrona subaspera, who in turn were consumed by the fur seals. Thus, the particles were accumulated both by the fish and the seals in the usual process of their feeding.  相似文献   

7.
In January–February 1991, about 1 million m3 of crude oil were released into the Arabian Gulf as a means of ecological warfare. A stretch of 644 km along the Saudi Arabian coast was heavily polluted over a width between a few meters and more than one kilometer. In four studies performed between March 1991 and April 1993 the state of representative areas of the affected coast was examined with the result that only minor changes were found in those oiled zones which are seldom inundated by the tides. Technical measures up to 1993 did not exceed the test level. A biological regeneration process is in progress which was not recognized as such in analyses of previous coastal oil pollution. Cyanobacterial mats, containing hydrocarbon-degrading bacteria, grow on oiled sediments which are regularly reached by tidal water. Shrinking and fracturing of the stable tar crusts starts a process of loosening and degrading of aged hydrocarbons.  相似文献   

8.
An oil spill occurred off Goa, west coast of India, on 23 March 2005 due to collision of two vessels. In general, fair weather with weak winds prevails along the west coast of India during March. In that case, the spill would have moved slowly and reached the coast. However, in 2005 when this event occurred, relatively stronger winds prevailed, and these winds forced the spill to move away from the coast. The spill trajectory was dominated by winds rather than currents. The MIKE21 Spill Analysis model was used to simulate the spill trajectory. The observed spill trajectory and the slick area were in agreement with the model simulations. The present study illustrates the importance of having pre-validated trajectories of spill scenarios for selecting eco-sensitive regions for preparedness and planning suitable response strategies whenever spill episodes occur.  相似文献   

9.
富油煤原位热解的油、气等产物可通过开采形成的压裂缝进入地下环境,产生一系列环境行为。为进一步了解富油煤热解产物在地下环境中的自然降解与挥发行为,选择粉砂作为典型土壤,以富油煤热解焦油为典型污染物,开展了煤焦油5种组分在粉砂中的自然降解和挥发行为研究,建立了2种环境行为的动力学模型;进一步考察了温度、污染物初始质量浓度等因素对自然降解与挥发的影响。结果表明,煤焦油各组分在粉砂中的降解效果顺序为,酚油>洗油>萘油>沥青>蒽油,且粉砂中各组分的自然降解符合一级动力学方程。其中,酚油的降解速率常数最大,为6.18×10−3;而蒽油的半衰期最长,达到了228 d;温度35 ℃时的降解率为67%,初始质量浓度为10 g·kg−1时,降解率高达72%。粉砂中煤焦油的挥发符合Elovich方程,各组分在粉砂中的挥发效果顺序为,酚油>萘油>洗油>蒽油>沥青。其中,酚油的挥发率是沥青挥发率的4倍;酚油在35 ℃时的挥发率是15 ℃的1.2~2.5倍,污染物初始质量浓度对煤焦油各组分的挥发影响较小。本研究结果可为开展原位开采引起的地下水环境污染控制与修复提供参考。  相似文献   

10.
Most of the shores in Qatar and other oil producing countries have had a long history of crude oil pollution from different sources. This pilot study was to assess the problem and suggest a management programme for disposing of the collected tar or lessening the impact of tar accumulation. The vegetation on the sites used for dumping tar was used in a field survey to identify bioindicators of tar pollution and of the natural recovery of polluted sites. The phytomonitoring results indicate that recovery of polluted sites can be quite rapid after clean-up and restoration. To facilitate natural plant invasion and colonization, and the restoration of tar piles, the dumping sites must have plant communities with high species diversity and a high percentage of annual plants. Depending on the sand-tar ratio in the piles, artificial seeding of selected plant species (listed) can be applied by using species mixes or single species seeding. Management techniques are suggested to optimize the natural recovery and revegetation of tar-affected coastal marshes.  相似文献   

11.
Plastic production pellets collected from beaches of south west England contain variable concentrations of trace metals (Cr, Co, Ni, Cu, Zn, Cd and Pb) that, in some cases, exceed concentrations reported for local estuarine sediments. The rates and mechanisms by which metals associate with virgin and beached polyethylene pellets were studied by adding a cocktail of 5 μg L(-1) of trace metals to 10 g L(-1) pellet suspensions in filtered seawater. Kinetic profiles were modelled using a pseudo-first-order equation and yielded response times of less than about 100 h and equilibrium partition coefficients of up to about 225 ml g(-1) that were consistently higher for beached pellets than virgin pellets. Adsorption isotherms conformed to both the Langmuir and Freundlich equations and adsorption capacities were greater for beached pellets than for virgin pellets. Results suggest that plastics may represent an important vehicle for the transport of metals in the marine environment.  相似文献   

12.
The study aims to investigate hydrocarbon and pollutant concentrations in the southern coastal waters of the Caspian Sea to trace their origins and nature, including the effect of the beach materials on hydrocarbons for 11 sites in Golestan, Mazandaran, and Guilan provinces. Samples were collected from sandy and rocky sites for gas chromatography in five carbon ranges of gasoline, diesel oil, engine oil, BTEX, and PAH. The GC analysis revealed the highest pollutant concentration levels in autumn and the lowest in summer; moreover in rocky beaches analysis indicated that a major portion of the oil pollution in the region consists of hydrocarbons.  相似文献   

13.
During the period July, 1977 to September, 1979, rainfall was collected in the vicinity of the Kennedy Space Center, Florida and subjected to appropriate chemical analysis for purposes of characterization of general composition and acidity. Results obtained form the basis for future comparisons, should significant alteration of the chemical composition of rain occur during the space shuttle era. Acidity extremes calculated on a monthly basis from event samples collected from five sites within a 200 km2 area varied from pH 5.1 in November, 1977 and April, 1978 to pH 4.3 in July, 1978 and July, 1979. Weighted average pH for the entire period was 4.55. Acidity was due to the presence of sulfuric and nitric acids. The mole ratio of excess SO4−2:NO3 was typically greater than one. Monthly weighted average Cl concentrations ranged from 20–240 micromoles/liter. The Cl :Na+ ratio was slightly lower than that present in sea water. The sample collection network was expanded during 16 months of the study to include 13 sites situated within a 600km2 area. Monthly weighted average acidity and concentrations of other ions present in rain, based on samples collected from the five site network, agreed closely with corresponding concentrations determined from samples collected in the entire 13 site network.  相似文献   

14.
Lebanon in general and its capital, Beirut, suffer from water shortage due to the increasing water demand and the lack of proper management despite its abundant water resources. An intermittent water supply strategy was implemented in order to minimise deficiency problems. This, however, can seriously affect water quality due to the potential suction of non-potable water by negative pressures, biofilm detachment, and microbial re-growth especially when static conditions occur. Intermittent supplies also entail storing water in household tanks to satisfy demand during no-flow periods, and these tanks often encourage bacterial re-growth. Dumping of disinfectants in order to circumvent bacterial presence and the subsequent formation of undesirable byproducts is another concern. A study was conducted in Beirut over an eight-month period, during which samples were collected from household tanks and drinking water taps of Beirut's network. This paper presents the findings of the study and highlights key aspects in intermittent water supply systems.  相似文献   

15.
Artificial leaf packs were used to determine the effects of an oil spill on stream macroinvertebrate communities in the Chariton River, Missouri. Plastic mesh leaf retainers with approximately 10 g of leaves from five tree species were deployed at five sites (two upstream of the spill and three downstream) immediately after the spill and one year later. Four macroinvertebrate species dominating the community at upstream sites were virtually eliminated below the spill, including the stonefly Isoperla bilineata, the caddisfly Potamyia flava, the midge Thienemanniella xena, and blackfly larvae (Simulium sp.). Density of collector and shredder functional groups, and number of shredder taxa differed between upstream sites and the two furthest downstream sites during the 1990 sample period (Kruskal-Wallis w/Bonferroni paired comparisons, experiment wise error rate = 0.05). With one exception, no differences between sites were detected in the 1991-1992 sample period, indicating that the benthic community had at least partially recovered from the oil spill after one year. The odds of obtaining a sample with a small abundance of shredders (abundance < median) in 1990 was significantly greater downstream of the spill than upstream, and the odds of obtaining a sample with a small abundance of shredders at downstream sites was greater in 1990 than in 1991-1992. A similar pattern was observed in abundance and taxa richness of the collector functional group. No significant differences between the two sampling periods were detected at upstream sites. Observed effects appeared to be associated with oil sorption and substrate coating, creating conditions unsuitable for successful colonization.  相似文献   

16.
程凌云  孟棒棒  岳波  张颖  林晔 《环境工程学报》2023,17(11):3670-3680
为了评价进口再生塑料颗粒中主要重金属经口摄入的潜在健康风险,选取了5类典型进口再生塑料颗粒,基于美国环保署(US EPA)人体健康风险评估框架,通过检测其在食物模拟液中Hg、Pb、Cr、Cd、Mn和Cu的浸出浓度,对其饮食摄入途径下的致癌/非致癌风险进行量化评价,并采用靶器官毒性剂量(TTD)法对非致癌风险指数进行修正。结果表明,参照我国饮用水标准,Hg、Pb、Cr、Cd和Mn浸出浓度超标倍数分别高达1 243.04、50.06、38.27、3.27和2.96倍,而Cu未超标,总体上存在严重健康风险。致癌风险结果显示,在所有模拟场景下,5种进口再生塑料颗粒中重金属致癌风险指数平均超过可能致癌水平上限70.28倍。非致癌风险结果显示,在所有模拟场景下,5种进口再生塑料颗粒中重金属传统非致癌风险指数和靶器官毒性剂量修正的非致癌风险指数分别平均超过最高上限15.26倍和23.71倍,其中肠胃道、血液、肾脏和神经系统存在不可接受非致癌风险,睾丸、心血管和肝脏不存在非致癌风险。这表明进口再生塑料颗粒所带来潜在健康风险仍需持续关注。  相似文献   

17.
Since current estimates of hexachlorobenzene (HCB), polychlorinated biphenyls (PCB), dioxins (PCDD) and furans (PCDF) from ships are based on a relatively limited and old data set, an update of these emission factors has been outlined as a target towards improved Swedish emission inventories. Consequently, a comprehensive study was undertaken focusing on these emissions from three different ships during December 2003 to March 2004. Analyses were performed on 12 exhaust samples, three fuel oil samples and three lubricating oil samples from a representative selection of diesel engine models, fuel types and during different “real-world” operating conditions.The determined emissions corresponded reasonably well with previous measurements. The data suggest however that previous PCDD/PCDF emission factors are somewhat higher than those measured here. As expected the greatest emissions were observed during main engine start-up periods and for engines using heavier fuel oils. Total emissions for 2002, using revised emission factors, have been calculated based on Swedish sold marine fuels and also for geographical areas of national importance. In terms of their toxic equivalence (WHO-TEQ), the PCDD/PCDF emissions from ships using Swedish fuels are small (0.37–0.85 g TEQ) in comparison to recent estimates for the national total (ca. 45 g TEQ). Emissions from other land-based diesel engines (road vehicles, off-road machinery, military vehicles and locomotives) are estimated to contribute a further 0.18–0.42 g TEQ. Similarly, HCB and PCB emissions from these sources are small compared to 1995 national emission inventories.  相似文献   

18.
Separation of heavier-than-water plastic mixtures had been investigated via the fluidization of their packed beds induced by an upward flow of water. The samples examined were resin pellets and crushed plastic products including PVC, PET and PBT. On the onset of a flow, a mixed bed was swelled to the state of fluidization and separated into layers of respective resins depending on their density. The effects of the flow rate, an amount of the samples and their density difference were examined on the separation of resin pellets. Under an appropriate condition, the process was completed within a few minutes, and satisfactory separation was attained when the density difference of the samples exceeded 0.05 g cm-3. By using a column equipped with several sample outlets sorted resins could be recovered with their purity intact by withdrawing each layer successively from above through a suitable outlet. Multi-stage separation was also found to be effective in treating close-density samples. Compared with uniform-sized resin pellets, size distribution of crushed plastic samples deteriorated the separation to some extent.  相似文献   

19.
Plastic debris were collected from eight beaches around San Diego County, California. Debris collected include: pre-production pellets and post-consumer plastics including fragments, polystyrene (PS) foam, and rubber. A total of n = 2453 pieces were collected ranging from <5 mm to 50 mm in size. The plastic pieces were separated by type, location, and appearance and analyzed for polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT) and its breakdown products, and chlordanes. PAH concentrations ranged from 30 ng g−1 to 1900 ng g−1, PCBs from non-detect to 47 ng g−1, chlordanes from 1.8 ng g−1 to 60 ng g−1, and DDTs from non-detect to 76 ng g−1. Consistently higher PAH concentrations found in PS foam samples (300-1900 ng g−1) led us to examine unexposed PS foam packaging materials and PS virgin pellets. Unexposed PS foam contained higher concentrations of PAHs (240-1700 ng g−1) than PS virgin pellets (12-15 ng g−1), suggesting that PAHs may be produced during manufacturing. Temporal trends of debris were investigated at one site, Ocean Beach, where storm events and beach maintenance were found to be important variables influencing debris present at a given time.  相似文献   

20.
The shipping industry has been an unrecognized source of criteria pollutants: nitrogen oxides (NOx), volatile organic compounds, coarse particulate matter (PM10), fine particulate matter (PM2.5), sulfur dioxide (SO2), and carbon monoxide (CO). Liquefied natural gas (LNG) has traditionally been transported via steam turbine (ST) ships. Recently, LNG shippers have begun using dual-fuel diesel engines (DFDEs) to propel and offload their cargoes. Both the conventional ST boilers and DFDE are capable of burning a range of fuels, from heavy fuel oil to boil-off-gas (BOG) from the LNG load. In this paper a method for estimating the emissions from ST boilers and DFDEs during LNG offloading operations at berth is presented, along with typical emissions from LNG ships during offloading operations under different scenarios ranging from worst-case fuel oil combustion to the use of shore power. The impact on air quality in nonattainment areas where LNG ships call is discussed. Current and future air pollution control regulations for ocean-going vessels (OGVs) such as LNG ships are also discussed. The objective of this study was to estimate and compare emissions of criteria pollutants from conventional ST and DFDE ships using different fuels. The results of this study suggest that newer DFDE ships have lower SO2 and PM2.5/PM10 emissions, conventional ST ships have lower NOx, volatile organic compound, and CO emissions; and DFDE ships utilizing shore power at berth produce no localized emissions because they draw their required power from the local electric grid.  相似文献   

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