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Sea Nine 211 as antifouling biocide: A coastal pollutant of emerging concern

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Journal of Environmental Sciences 2017年第11期29卷 68-79页

作者： Lianguo chen James c.w.lam State key Laboratory in Marine Pollution City University of Hong Kong Department of Science and Environmental Studies The Education University of Hong Kong

Sea Nine 211, with 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one（DcOIT） being the biocidal ingredient, is a widely-used antifouling agent to deter the undesirable biofouling phenomenon. It is commercially promoted as an environmentally acceptable antifoulant mainly due to its claimed rapid degradation in marine environment. However, increasing researches document varying degradative kinetics in different environments, proving that Sea Nine 211 is actually not degraded equally fast around the world（half-life between〈 1 day and 13.1 days）. Large-scale application of Sea Nine 211 in antifouling coatings has also caused global contamination of marine environment in various compartments. For example, accumulation of Sea Nine 211 is detected as high as 3700 ng/L in Spanish seawater and 281 ng/g dry weight in korean sediment. considering that Sea Nine 211 is highly toxic against non-target marine organisms, environmental risk assessment finds that most marine organisms are endangered by Sea Nine 211 in worst-case scenario. Its endocrine disrupting and reproductive impairing effects at environmentally worst-case concentrations further constitute a long-term threat to the maintenance of population ***, in the light of the varying degradability, environmental pollution and high toxicity, especially the endocrine disruption, Sea Nine 211 as an antifouling agent is likely to cause non-negligible damages to the marine ecosystem. There is an urgency to perform a systematic ecological risk assessment of Sea Nine 211 to prevent the potential impacts on the health of marine environment. A regular monitoring also becomes necessary to place the usage of antifouling biocides under control.

关键词： Sea Nine 211 Antifouling agent Degradation Environmental occurrences Ecological risks Endocrine disruption

chemical characteristics of aerosols at coastal station in Hong kong.Ⅱ. Environmental behavior of trace elements during the April 1995 to April 1996

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Journal of Environmental Sciences 2004年第2期16卷 212-221页

作者： k.S.lam Z.L.cheng S.c.kot c.w.Tsang Department of civil and Structural Engineering the Hong Kong Polytechnic UniversityResearch Center for Eco-Environmental Sciences Chinese Academy of SciencesDepartment of Mechanical Engineering The Hong Kong University of Science & Technology Clear Water BayDepartment of Applied Biology and Chemical Technology the Hong Kong Polytechnic University Hung Hom Hong Kong ChinaBeijing 100085 ChinaHong Kong ChinaHung Hom Hong Kong China

An one-year of sampling aerosol program was carried out during the period of April 1995 to April 1996 at coastal region, cape D′Aguilar, in Hong kong. The trace element composition of aerosol particles(TSP and PM 10 ) were measured and analyzed by using the Instrumental Neutron Activation Analysis(INAA) and Inductive couple Plasma-Mass Spectrometry(IcP-MS) techniques. The results showed that the polluted elements such as: V, Zn, As, Pb, cd, Sb, I, Se, Bi, with high enrichment factor(E.F) values, are derived from anthropogenic sources, while Sc, Al, Fe, Mn, Sm, La, Sr are less than 10 in E.F, these elements are related the crust and soil. The concentration of the trace elements are present seasonal variation i.e. summer low and winter high, whereas the V or noncrustal V(V *) present summer high and winter low, this phenomenon might be explained by local or regional oil combustion sources. Use three type of elemental ratio, e.g. La/Sm, Mn */V * and Bi/Al indicate that both TSP and PM 10 of La/Sm ratios are mainly related to soil and dust, Mn */V * are probably represent fossil combustion and Bi/Al are possibly associated with refuse incineration, ferromanganese alloys and aluminum production. The varimax rotation factor analysis for trace elements was performed. By means of the absolute principal component analysis(APcA) and multiple regression, the contribution of trace elements to possible sources and overall means of trace elements were estimated. The results showed that the present station is impacted by the anthropogenic species, although the quantities are different during the summertime and wintertime.

关键词： TSP PM 10 trace elements enhancement factor element ratios seasonal variation factor analysis

Long-term temporal-spatial dynamics of marine coastal water quality in the Tolo Harbor,Hong kong,china

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Journal of Environmental Sciences 2004年第1期16卷 161-166页

作者： XUFu-liu k.c.lam R.w.Dawson TAOShu Y.D.cHEN DepartmentofUrbanandEnvironmentalSciences＆MOELaboratoryforEarthSurfaceProcess PekingUniversityBeijing100871China DepartmentofGeographyandResourceManagement TheChineseUniversityofHongKongShatinNewTerritoriesHongKongChina

The long-term temporal and spatial dynamics of marine coastal water quality in Tolo Harbor, Hong kong were explored. The Harbor is divided into three zones represented as Harbor, Buffer, and channel Subzones. The time range for the study covers the period from the 1970s to the 1990s. The selected indicators for the comprehensive assessment of water quality consist of physical, chemical and biological aspects, including suspended solids(SS), Secchi disk depth(SD), 5-day biochemical oxygen demand(BOD\-5), total nitrogen(TN), total phosphorus(TP), faecal coliform, chlorophyll-a(chl-a), and the number of red tide occurrences. The results indicated the presence of obvious temporal and spatial trends with regard to changes in water quality. Spatially, water quality in the channel Subzone is the best, while that in the Harbor Subzone is the worst. On a temporal basis, the average trend from bad to good was 1980s>1990s>1970s as indicated by most of the selected water quality indicators. water quality during the late 1980s reached its worst level with the lowest SD, the highest BOD\-5, TN, TP, chl-a concentrations, and the number of red tide occurrences. These long-term temporal-spatial water quality trends were also found in other studies of the Tolo Harbor. The large quantity of pollutants produced as a result of increasing population, industrial and commercial actives, and urbanization and industrialization trends in both Shatin and Tai Po seem to be primarily responsible for the changes in marine coastal water quality.

关键词： temporal-spatial dynamics water quality indicators pollution load Tolo Harbor

On the Variability and correlation of Surface Ozone and carbon Monoxide Observed in Hong kong Using Trajectory and Regression Analyses

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Advances in Atmospheric Sciences 2004年第1期21卷 141-152页

作者：王体健 k.S.lam c.w.TSANG S.c.kOT Department of Atmospheric Sciences Nanjing University Nanjing 210093 Environmental Engineering Unit Department of Civil & Structural Engineering The Hong Kong Polytechnic University Hong Kong Environmental Engineering Unit Department of Civil & Structural Engineering The Hong Kong Polytechnic University Hong Kong Department of Mechanical Engineering Hong Kong University of Science & Technology Hong Kong

This paper investigates, the variability and correlation of surface ozone (Os) and carbon monoxide (cO) observed at cape D'Aguilar in Hong kong from 1 January 1994 to 31 December 1995. Statistical analysis shows that the average O3 and cO mixing ratios during the two years are 32±17ppbv and 305±191 ppbv, respectively. The O3/cO ratio ranges from 0.05 to 0.6 ppbv/ppbv with its frequency peaking at 0.15. The raw dataset is divided into six groups using backward trajectory and cluster analyses. For data assigned to the same trajectory type, three groups are further sorted out based on cO and NOX mixing ratios. The correlation coefficients and slopes of O3/cO for the 18 groups are calculated using linear regression analysis. Finally, five kinds of air masses with different chemical features are identified: continental background (cB), marine background (MB), regional polluted continental (RPc), perturbed marine (P*M), and local polluted (LP) air masses. Further studies indicate that O3 and cO in the continental and marine background air masses (cB and MB) are positively correlated for the reason that they are well mixed over the long range transport before arriving at the site. The negative correlation between O3 and cO in air mass LP is believed to be associated with heavy anthropogenic influence, which results from the enhancement by local sources as indicated by high cO and NOx and depletion of O3 when mixed with fresh emissions. The positive correlation in the perturbed marine air mass P*M favors the low photochemical production of O3. The negative correlation found in the regional polluted continental air mass RPc is different from the observations at Oki Island in Japan due to the more complex O3 chemistry at cape D'Aguilar.

关键词： ozone carbon monoxide trajectory

Occurrence and fate of endogenous steroid hormones,alkylphenol ethoxylates, bisphenol A and phthalates in municipal sewage treatment systems

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Journal of Environmental Sciences 2017年第11期29卷 49-58页

作者： Qian wu James c.w.lam karen Y.kwok Mirabelle M.P.Tsui Paul k.S.lam State key Laboratory in Marine Pollution (SkLMP) Department of Biology and Chemistry Research Centre for the Oceans and Human Health Shenzhen Key Laboratory for Sustainable Use of Marine Biodiversity City University of Hong Kong Department of Science and Environmental Studies The Education University of Hong of Kong

Steroid hormones, alkylphenol ethoxylates（APEOs） and phthalic acid esters（PAEs） are emerging endocrine disrupting chemicals（EDcs） that can interfere with the endocrine function in organisms at low concentrations. The occurrence, distribution behavior, removal rate and the fate of 31 target EDcs in sewage treatment plants, which consist of various treatment facilities and receiving water in Hong kong, were investigated. Estrone,nonylphenol-di-ethoxylate and diethyl phthalate were found to be dominant in each group of influent samples with concentrations ranging from 11–33, 747–3945 and 445–4635 ng/L,respectively. conversely, progesterone, nonylphenol-mono-ethoxylate and bis（2-ethylhexyl）phthalate were the most abundant in dewatered sludge, with concentrations ranging from 0.9–237, 75–19,743 and 4310–37,016 ng/g（dry weight）. The removal rates of primary sedimentation and disinfection approaches were lower than 30% for most of the chemicals,while those of activated sludge and reverse osmosis were greater than 80% for more than two-thirds of the compounds, noticeably decreasing the estrogenic risk of sewage discharged into the environment. Steroid hormones were removed via biological degradation, while some APEOs and PAEs adsorbed to the sludge. Victoria Harbor poses a low to medium estrogenic risk mainly contributed by estrone and estradiol and deserves attention.

关键词： Endocrine disruptor Steroid hormone Alkylphenol ethoxylate Phthalic acid ester Risk assessment

Amine-catalyzed polycyclotrimerization of arylene bipropiolate:A metal-free and regioselective route to hyperbranched polymer

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Science china chemistry 2008年第8期51卷 705-708页

作者： JIM cathy k w lam Jacky w Y HAEUSSLER Matthias Department of chemistry The Hong Kong University of Science & TechnologyClear Water BayKowloonHong KongChina

This paper presents a new synthetic route to hyperbranched polymer. An arylene bipropiolate monomer,dimethylmethylenebis(1,4-phenylene) bipropiolate,was prepared by a one-step esterification reaction of bisphenol A with propiolic acid. Polycyclotrimrtization of the monomer was effected by reflux in dimethylformamide(DMF),producing a soluble hyperbranched poly(aroxycarbonylphenylene) in a good yield. The polymer was perfectly branched with a degree of branching of 100%.

关键词： cyclotrimerization regioselectivity hyperbranched polymer

Restorating marine coastal ecosystem health as a new goad for integrated catchment management in Tolo Harbour,Hong kong,china

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chinese Journal of Population,Resources and Environment 2004年第2期2卷 11-19页

作者： lam k.c. Department of Geography and Resoure management The Chinese University of Hong Kong.ShatinNew TerritoriesHong KongChinahe paper demonstrates why it is necessary to take the restoration of marine coastal ecosystem health as a new goal for integrated catchment management in coastal area of the Tolo Harbour. The present goal of integrated catchment management (ICM) in the Tolo Harbour is to meet with Water Quality Objectives. The performance of an ICM plan Tolo Harbour Action Plan (THAP) is evaluated by using marine coastal ecosystem health indicators including stress indicators and responses indicators. Since the implementation of THAP in 1988 some significant reduction in pollution loading has been observed - reduction of 83 % of BOD load and 82 % of TN between 1988 and 1999. There has been an improvement in the health state of Tolo Harbour marine coastal ecosystem as evidenced in the trends of the physical chemical and biological indicators although some reverse fluctuations in some periods exist. However this can only be considered as the first sign of the ecosystem health restoration since ecosystem health covers not only physical chemical and biological aspects of an ecosystem but also ecosystem-service-function aspect. It is recommended to take the restoration and protection of marine coastal ecosystem health as a new goal instead of water quality objective management for integrated catchment management in Tolo Harbour catchment. Steps to further improve the marine coastal ecosystem health of Tolo harbour are discussed in the paper.

The paper demonstrates why it is necessary to take the restoration of marine coastal ecosystem health as a new goal for integrated catchment management, in coastal area of the Tolo Harbour. The present goal of integrated catchment management (IcM) in the Tolo Harbour is to meet with water Quality Objectives. The performance of an IcM plan, Tolo Harbour Action Plan (THAP), is evaluated by using marine coastal ecosystem health indicators including stress indicators and responses indicators. Since the implementation of THAP in 1988, some significant reduction in pollution loading has been observed - reduction of 83 % of BOD load and 82 % of TN between 1988 and 1999. There has been an improvement in the health state of Tolo Harbour marine coastal ecosystem as evidenced in the trends of the physical, chemical and biological indicators, although some reverse fluctuations in some periods exist. However, this can only be considered as the first sign of the ecosystem health restoration, since ecosystem health

关键词： Marine coastal ecosystem health integrated catchment management pollution loading indicator Tolo Harbour Action Plan.

Synthesis and properties of poly(1-phenyl-1-octyne)s containing stereogenic and chromophoric pendant groups

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Science china chemistry 2009年第10期52卷 1691-1702页

作者： lam Jacky w.Y. JIM cathy k.w. kwOk Hoi Sing Department of chemistry The Hong Kong University of Science & Technology center for Display Research The Hong Kong University of Science & Technology

Poly(1-phenyl-1-octyne)s containing different stereogenic and chromophoric pendants {-[(c6H13)c= c(c6H4-p-cO2-R)] n -R = [(1S)-endo]-(?)-borneyl (P3), (1R,2S,5R)-(?)-menthyl (P4), -c6H4-p-(1R,2S,5R)-(?)-menthyl (P5), 2-napthyl (P6), 4-biphenylyl (P7)} have been designed and synthesized. The polymers are prepared in moderate yields by wcl6-Ph4Sn and possess high molecular weights (M w up to 64000). The structures and properties of the polymers are characterized and evaluated by NMR, TGA, UV, cD, PL, and EL analyses. All the polymers are thermally stable and their temperatures for 5% weight loss locate in the range of 300 to 416°c under nitrogen. The energy band gaps of all the polymers are ～3.0 eV. Polymers P4 and P5 show cD absorptions associated with the helicity of the polymer segments. Excitation of the THF solutions of P3–P7 by UV irradiation gives strong blue lights of ～485 nm with quantum yields higher than 20%. The thin films of the polymers also emit in the same spectral region, indicative of little aggregation-caused quenching of light emission. Multilayer EL devices with a configuration of ITO/Polymer:PVk/BcP/Alq3/LiF/Al are constructed, which emit blue lights of ～487 nm. The maximum luminance and external quantum efficiency vary with the pendant groups, with P6 exhibiting the highest external quantum efficiency of 0.16%. The spectra stability of the EL devices is outstanding and the EL peak maximum experiences little change with the applied voltage.

关键词： chiral photoluminescence polyacetylene electroluminescence helicity

childhood Langerhans cell histiocytosis:a disease with many faces

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world Journal of Pediatrics 2019年第6期15卷 536-545页

作者： Alexander k.c.Leung Joseph M.lam kin Fon Leong Department of Pediatrics The University of Calgaryand The Alberta Children's Hospital#20023316th Avenue NWCalgaryAB T2M 0H5Canada Department of Pediatrics University of British ColumbiaVancouverBCCanada Department of Dermatology and Skin Sciences University of British ColumbiaVancouverBCCanada Pediatric Institute Kuala Lumpur General HospitalKuala LumpurMalaysia

Background Langerhans cell histiocytosis(LcH)is a group of diseases characterized by the proliferation and accumulation of Langerhans *** presentations of LcH vary *** sources A PubMed search was conducted using clinical Queries with the key term "Langerhans cell histiocytosis".The search strategy included meta-analyses,randomized controlled trials,clinical trials,observational studies,and *** paper is based on,but not limited to,the search *** Generally,patients with LcH can be divided into two groups based on the extent of involvement at diagnosis,namely,single-system LcH and multisystem *** involvement may be unifocal or *** with isolated bone lesions typically present between 5 and 15 years of age,whereas those with multisystem LcH tend to present before 5 years of *** clinical spectrum is broad,ranging from an asymptomatic isolated skin or bone lesion to a life-threatening multisystem *** manifestations include,among others,"punched out" lytic bone lesion,seborrheic dermatitis-like erup-tion,erythematous/reddish-brown crusted/scaly papules/maculopapules/plaques/patches,and eczematous lesions,diabetes insipidus,hepatosplenomegaly,cytopenias,lymphadenopathy,and an acute fulminant disseminated multisystem condition presenting with fever,skin rash,anemia,thrombocytopenia,lymphadenopathy,and *** diagnosis is clinicopathologic,based on typical clinical findings and histologic/immunohistochemical examination of a biopsy of lesional *** cD1a,S100,and/or cD207(Langerin)immunohistochemical staining of lesional cells is required for a definitive *** waiting is recommended for patients with skin-only *** with symptomatic or refractory skin-only LcH may be treated with topical tacrolimus/corticosteroids,topical nitrogen mustard,oral methotrexate,or oral *** current recommended first-line therapy for patients with multisystem LcH i

关键词： cytopenia Diabetes insipidus Eczematous lesions Hepatosplenomegaly Lymphadenopathy Seborrheic dermatitis-like eruption