Utjecaj organskih i mineralnih sastojaka tla na sorpcijsko ponašanje klorfenolnih i triazinskih mikrozagađivala

This article compares the sorption behaviour of 2,4,6-trichlorophenol, 2,3,4,6-tetrachlorophenol, pentachlorophenol, chlorotriazine atrazine, methylthiotriazine ametryn, methoxytriazine atratone, hydroxyatrazine, and didelakylated atrazine in a topsoil and an aquifer sediment before and after removal of sorbent organic matter and in humic acid. Freundlich isotherm coeffi cients Kf and 1/n and free energy change (∆G°) were calculated for all compounds in all sorbents. According to sorbent pH values, chlorophenolate anions and uncharged triazine species dominated in all sorption experiments with topsoil and aquifer sediment. In experiments with humic acid, chlorophenols, atrazine, and didealkylated atrazine existed almost completely as neutral species, whereas protonated species dominated for hydroxyatrazine, atratone, and ametryn. In addition to a hydrophobic partition, sorption of all compounds in native soil and sediment sorbents includes specifi c, more polar interactions, which greatly depend on sorbate acidity/ basicity, specifi c properties of the sorbent organic matter and of mineral surface, as well as on the system pH. A signifi cantly greater sorption intensity of all compounds in “organic-free” than in the native aquifer sediment confi rmed the importance and possible dominance of mineral surface in the sorption process. Sorption intensity of chlorophenol and triazine compounds in humic acid was closely related to compound hydrophobicity. Greater sorption of almost completely protonated hydroxyatrazine than of the more hydropohobic but uncharged atrazine indicated different humic acid reaction sites for two compounds and consequently different sorption mechanisms.Uspoređena je sorpcija 2,4,6-triklorfenola, 2,3,4,6-tetraklorfenola i pentaklorfenola te različito supstituiranih triazinskih spojeva - klortriazina atrazina, metiltiotriazina ametrina, metoksitriazina atratona i razgradnih produkata atrazina hidroksiatrazina i didealkiliranog atrazina – u površinskom tlu i sedimentu vodonosnika prije i nakon uklanjanja organske tvari te u huminskoj kiselini. Izračunani su koefi cijenti Freundlichove izoterme Kf i 1/n te izmjena slobodne energije (∆G°) za sve spojeve i sorbense. U skladu s pH-vrijednostima sorbensa u svim su sorpcijskim pokusima s nativnim tlom i sedimentom prevladavali klorfenolatni anioni i neutralni triazinski spojevi. U pokusima s huminskom kiselinom klorfenoli, atrazin i didealkilirani atrazin postojali su kao neutralne vrste, dok su hidroksiatrazin, atraton i ametrin bili većim dijelom protonirani. Sorpcija svih spojeva u prirodnom tlu i sedimentu uključuje uz hidrofobnu particiju i specifi čne polarnije interakcije ovisne o kiselosti/bazičnosti sorbata, specifi čnim svojstvima organske tvari i mineralne površine sorbensa te o pH-vrijednosti sustava. Intenzitet sorpcije svih spojeva u sedimentu iz kojeg je uklonjena organska tvar bio je značajno veći od sorpcije u prirodnom sedimentu, što potvrđuje važnost i moguću dominantnu ulogu mineralne površine u sorpcijskom procesu. Intenzitet sorpcije klorfenola te klortriazina, metiltiotriazina i metoksitriazina u huminskoj kiselini korelirao je s hidrofobnosti spojeva. Veća sorpcija gotovo potpuno protoniranog hidroksiatrazina od hidrofobnijeg, ali neutralnog atrazina upućuje na različita reakcijska mjesta za ova dva spoja, a time i na različite mehanizme sorpcije u huminskoj kiselini

Ocjena izloženosti ljudi onečišćenjima na različitim lokacijama - povijesni pregled međunarodnog projekta HEAL

The first part of the review describes events and newly acquired knowledge that anticipated the making of the HEAL project and its preparatory phase. The pilot study relied on the belief that the total exposure assessment should take into account different pollutants and their relative contribution in the human intake from different environmental media such as air, drinking water, food chain, and soil. The pilot study included exposure assessment to lead and cadmium, nitrogen dioxide, hexachlorobenzene, and DDT-complex. Concurrently, another study on indoor air quality in Kenya and Gambia took place. In its second phase, the project evaluated the actual trends and outlined potential future directions. It was decided that the project should focus on the promotion of exposure studies, particularly in developing countries, and that it should establish a closer relation with health risk assessment and environmental epidemiology. The last part of the review describes the participation of the Institute for Medical Research and Occupational Health in the project and in related research activities performed after the pilot phase.Pregled je podijeljen u nekoliko dijelova. Prvo se govori o zbivanjima i saznanjima koja su dala podlogu za osmišljavanje programa te o pripremnim radovima koji su obavljeni da bi se projekt počeo ostvarivati. Polazna pretpostavka za pokretanje projekta bila je ova: U ocjeni izloženosti različitim onečišćenjima treba uzeti u obzir sve medije okoliša u kojem ljudi borave i djeluju (zrak, voda za piće, hrana, tlo). Unos onečišćenja u čovjeka mora se mjeriti što je moguće direktnije, kako bi se dobila realna slika o unosu i opterećenju organizma određenim onečišćenjem. Pri tome je važan uvid u relativnu participaciju pojedinih medija u okolišu u ukupnom unosu. Realna ocjena izloženosti bitna je karika u procjeni rizika te u usmjeravanju mjera zaštite i upravljanju okolišem. Za ostvarenje zacrtanih ciljeva i unapređenje i racionalizaciju pristupa u realnoj ocjeni izloženosti nužna je usklađena međunarodna suradnja. Projekt je i zamišljen kao međunarodni s time da se započne u nekoliko zemalja te da se u kasnijem tijeku proširi. U drugom dijelu pregleda prikazano je početno, usmjeravajuće razdoblje projekta (pilot phase). Taj je dio uključio ocjenu izloženosti teškim metalima (olovo, kadmij), dušikovu dioksidu (NO2) te organoklornim pesticidima (heksaklorobenzen – HCB, DDT kompleks). Sudjelovale su ove zemlje: SAD, Švedska, Hrvatska (u sastavu tadašnje Jugoslavije), Brazil, Japan i Kina. Započelo je s kontrolom kvalitete laboratorijskih postupaka (analiza) da bi se nakon toga – slijedeći precizno dogovoreni program – pristupilo ocjeni izloženosti onečišćenjima zraka u zatvorenim prostorima (indoor air) povezano s uporabom otvorenih ognjišta u Keniji i Zambiji. Sljedeći dio pregleda odnosi se na prikaz zbivanja do kojih je došlo nakon provedene prve, »pilot« faze projekta. Razmatrale su se mogućnosti proširenja programa uključenjem drugih aktualnih onečišćenja. Posebno je razmatran problem organizacije učinkovite kontrole kvalitete laboratorijskih nalaza. Iskrsle su, naime, realne teškoće organizacijske i financijske prirode. U nastavku se govori o evaluaciji postojećeg stanja projekta i njegovu daljem usmjerenju, odnosno određenoj preorijentaciji i odlukama koje su s tim u vezi donesene. Projekt je utro putove suvremenim shvaćanjima o postupcima koje treba poduzimati da bi se dobila realna ocjena izloženosti, što treba povezivati s ocjenom rizika i epidemiološkim ispitivanjima. U vezi s tim utvrđeni su i praktični zadaci, nabrojeni u pregledu, na kojima bi u okviru međunarodne suradnje trebalo raditi u predstojećem razdoblju. Završni dio pregleda prikazuje sudjelovanje Instituta za medicinska istraživanja i medicinu rada u projektu. Uz opis sudjelovanja Instituta u »pilot« fazi, o čemu je prethodno bilo govora, izložena su ukratko i druga ispitivanja koja su u odnosu na ocjenu izloženosti u međuvremenu provedena. To se tiče dodatnih istraživanja o ocjeni izloženosti metalima, posebno olovu, zatim perzistentnim organoklornim spojevima, razvoja pasivnih skupljača uzoraka zraka za ocjenu osobne izloženosti dušikovu dioksidu, ocjene izloženosti trikloretilenu i tetrakloretilenu te amonijaku u skupinama stanovništva u Zagrebu, pa formaldehidu u dječjim vrtićima i osnovnim školama također u Zagrebu. Istraživana je i izloženost radionuklidima 137Cs i 90Sr u prehrambenom lancu stanovnikâ Hrvatske. Radilo se i na ocjeni rizika u odnosu na pojavu raka dišnih i probavnih organa u vezi s izloženošću azbestu. Na kraju pregleda navodi se publikacija, koja je nedavno (1996.) objavljena u izdanju HAZU, u kojoj su sabrani rezultati provedenih ispitivanja u okolišu u Hrvatskoj (razdoblje 1980.–1995.) te o mogućim učincima tih onečišćenja na zdravlje ljudi

Trače Enrichment of Polychlorinated Biphenyls in Soil: Efficiency of Sonicated Liquid-solid Extraction with Acetone/n-Hexane Mixture from Different Soil Types

The efficiency and reproducibility of an analytical procedure for trace determination of polychlorinated biphenyls (PCBs) in soil/sediment samples were evaluated by analyses of soils differing in their sorption-controlling properties. PCBs were accumulated from soil by sonicated multiple extraction with a 1:1 acetone/n-hexane mixture. The extracts, purified by treatment with copper powder, mercury, and sulphuric acid were analyzed by gas chromatography. The extraction efficiency from a soil spiked with 4-430 μg kg-1 of Aroclor 1242/Aroclor 1260 mixture depended on the initial PCB mass fraction. The matrix effect was evaluated by the analysis of PCBs added to five European reference soils differing in organic matter content, grain size distribution, mineral composition, pH values, and iron and aluminium oxides content. In four of these soils, a linear correlation was found between the slopes of calibration lines for the determination of PCBs and soil organic matter content. An exception was the most acidic soil with the highest, but poorly humified, organic matter. The linear regression of calibration line slopes and the content of soil fine silt particles indicated a positive, but not statistically significant, correlation

Ponašanje pesticida u vodenoj sredini. II. hidroliza diklorvosa u modelnom sistemu i u riječnoj vodi

An attempt has been made to elucidate the unusually fast decay of dichlorvos in the water of the Kupa river as compared to the behaviour of this pesticide in other river waters. The effects of pH, temperature, different ion species, organic components and concentration of dichlorvos on the decay rate were tested in a model system. The concentration of hydrogen ions and temperature were found to be rate determining. Different ion species could have a considerable effect on the rate of hydrolysis of dichlorvos but only if present in large quantities.Zapažena je vrlo brza razgradnja diklorvosa u vodi rijeke Kupe za razliku od ponašanja tog pesticida u vodi rijeke Save. U modelnom sustavu ispitani su utjecaji temperature, pH, različitih ionskih vrsta, organskih komponenti, te koncentracije diklorvosa na brzinu razgradnje diklorvosa. Temperatura i pH su faktori koji znatno utječu na brzinu razgradnje dok različite ionske vrste mogu imati značajan utjecaj samo ako su im koncentracije vrlo visoke. Usporedbom rezultata provedenih kemijskih analiza vode rijeka Save i Kupe nije nađeno nikakvo značajno odstupanje te je stoga teško izdvojiti ijedan ispitani kemijski pokazatelj kao osnovni uzrok brze razgradnje diklorvosa u vodi rijeke Kupe. Nasuprot tome biološki i bakteriološki profili ovih rijeka znatno se razlikuju te bi se brza razgradnja diklorvosa u vodi rijeke Kupe mogla objasniti njezinom većom moći samoočišćenja

Organochlorine Pesticides and Polychlorinated Biphenyls in Atmospheric Particles Collected in Zagreb, Croatia

We studied the occurrence and levels of hexachlorobenzene, α-, β-, and γ-hexachlorocyclo-hexane, 4,4\u27-DDT, 4,4\u27-DDE, 4,4\u27-DDD, and 17 PCBs (six indicator and eleven other toxicologically significant congeners) in PM10 and/or PM2.5 particle fractions collected between 2000 and 2003 and in 2010 at a site in the northern residential part of Zagreb, Croatia. Twenty-four-hour particle samples were collected on glass or quartz microfibre filters from approximately 100 m3 of ambient air per filter. Filters with particles collected over seven consecutive days were combined for ultrasonic extraction with 1:1 acetone:n-hexane mixture followed by capillary gas chromatography with electron capture detection. In the monitored periods, the mass concentrations of organochlorine compounds in atmospheric particles were characteristic of global environmental pollution and showed a decreasing trend. Local input was observed only for γ-hexachlorocyclohexane. There were no pronounced seasonal variations in the mass fraction levels of any pesticide or PCB in airborne particles. A decreasing trend in the mass concentrations of some compounds with higher air temperatures was mostly related to the lower particle concentrations in warmer seasons and, consequently, to less particle-bound organochlorine compounds in the atmosphere

Pesticides and other Persistent Organochlorine Compounds in the Environment in Croatia

Istraživanja podrijetla i raspodjele postojanih organoklorovih (OC) spojeva u okolišu u nas uključuju organoklorove (OC) pesticide, poliklorirane bifenile (PCB), poliklorirane dibenzop- dioksine (PCDD) i poliklorirane dibenzofurane (PCDF). Njihove razine ispituju se u površinskim, podzemnim i pitkim vodama, moru, riječnim i morskim sedimentima, tlu, zraku, oborinama te iglicama crnogoričnog drveća. U vodama su u proteklih dvadesetak godina najčešće detektirani pesticidi bili p,p’-DDT i njegovi metaboliti, gama-heksaklorcikloheksan (gama-HCH) i heksaklorbenzen. Najviše razine PCB-a izmjerene su u vodama krškog područja. Malobrojni podaci o OC spojevima u tlu/sedimentima upućuju na povišene razine PCB-a u tlu uz oštećene trafostanice i unutar zračnih luka. Razine PCDD-a i PCDF-a oko 50 puta više od onih tipičnih za seoska i urbana područja izmjerene su u tlu neposredno uz postrojenje kloralkalne elektrolize. OC pesticidi i PCB-i detektirani su u oborinama i zraku na području Zagreba te u iglicama crnogoričnog drveća na različitim lokacijama. Uočen je skorašnji unos gama-HCH i p,p’-DDT-ja u atmosferu. Najviše razine PCDD/PCDF-a u zraku na području Zagreba izmjerene su u industrijskom dijelu grada.Studies of origin and distribution of persistent environmental organochlorine (OC) pollutants in Croatia have comprised three groups of compounds: OC pesticides, polychlorinated biphenyls (PCB), and more recently polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF). The use of OC pesticides in Croatia is restricted, and hexachlorobenzene is even forbidden. PCBs may be used in closed systems only. The main source of PCDD/PCDF in the environment is combustion, but these also occur as byproducts in certain pesticide and other chemical formulations. Common to all those compounds are high hydrophobicity, poor solubility in water, and low volatility. They are rapidly and strongly sorbed by most soils and are often associated with bottom sediments in aquatic systems. Circulation of air masses, precipitation of particles onto which pollutants are sorbed, and wet depositions washing them out from the atmosphere may transport OC pollutants over long distances. The levels of persistent OC micropollutants in Croatia were investigated in surface, ground, and drinking water, sea water, river and marine sediments, soil, air, wet depositions, and coniferous tree needles. Most data collected for the last 20 years concern regular or periodical determination of OC pesticides in water. The most often detected compounds were p,p’-DDT and its metabolites, -hexachlorocyclohexane ( -HCH), and hexachlorobenzene. Recent measurements show that the concentrations of OC pesticides in different waters keep within the range of ecotoxicologically acceptable and legally prescribed values. The highest PCB levels (>100 ng/dm3) were measured in source and surface waters in karst areas where elimination of water pollutants by natural filtration through soil layers was almost negligible. The data on persistent OC compounds in soil and sediments are rare although, due to sorption and bioconcentration tendency, OC compounds are more likely to show higher levels in these media than in water. The most frequently detected OC pesticides in soils/sediments were the DDT-type compounds and -HCH. In most analysed soils and sediments PCB mass fractions were characteristic for global environmental pollution. Higher PCB levels were determined in soils collected in the close vicinity of transformer stations, in the airport areas, and close to some industrial plants. PCDD/PCDF levels in the airport soil kept within the range typical for urban and rural areas, whereas they rose by about 50 times in soils collected near a chloralkali electrolysis plant. Traces of OC pesticides and PCB were detected in wet depositions collected in urban and rural areas. The rain and snow samples collected in Zagreb contained traces of PCDD/PCDF and the highest concentrations at pg/dm3 level were measured for octa-CDD. The only data on OC pesticide, PCB and PCDD/PCDF levels in the ambient air were reported for air samples collected in 1997 and 1998 in the Zagreb city area. The highest pesticide concentrations were measured for -HCH. The highest PCDD/PCDF level was determined in the industrial zone of the city. The level of environmental pollution in a certain location can be evaluated through measurement of OC compounds in coniferous tree needles. All needle samples collected in the 1991–1998 period in different regions of Croatia contained OC pesticides and PCB. The mass fraction ratio _-HCH/_-HCH<1 found by the analysis of needle, air, and rain samples confirmed recent release of lindane in the environment as a consequence of its frequent local usage

Ponašanje pesticida u vodenoj sredini. II. hidroliza diklorvosa u modelnom sistemu i u riječnoj vodi

An attempt has been made to elucidate the unusually fast decay of dichlorvos in the water of the Kupa river as compared to the behaviour of this pesticide in other river waters. The effects of pH, temperature, different ion species, organic components and concentration of dichlorvos on the decay rate were tested in a model system. The concentration of hydrogen ions and temperature were found to be rate determining. Different ion species could have a considerable effect on the rate of hydrolysis of dichlorvos but only if present in large quantities.Zapažena je vrlo brza razgradnja diklorvosa u vodi rijeke Kupe za razliku od ponašanja tog pesticida u vodi rijeke Save. U modelnom sustavu ispitani su utjecaji temperature, pH, različitih ionskih vrsta, organskih komponenti, te koncentracije diklorvosa na brzinu razgradnje diklorvosa. Temperatura i pH su faktori koji znatno utječu na brzinu razgradnje dok različite ionske vrste mogu imati značajan utjecaj samo ako su im koncentracije vrlo visoke. Usporedbom rezultata provedenih kemijskih analiza vode rijeka Save i Kupe nije nađeno nikakvo značajno odstupanje te je stoga teško izdvojiti ijedan ispitani kemijski pokazatelj kao osnovni uzrok brze razgradnje diklorvosa u vodi rijeke Kupe. Nasuprot tome biološki i bakteriološki profili ovih rijeka znatno se razlikuju te bi se brza razgradnja diklorvosa u vodi rijeke Kupe mogla objasniti njezinom većom moći samoočišćenja

Environmental Monitoring and Analysis of Persistent Organic Pollutants

Persistent organic pollutants (POPs) are a group of 28 toxic compounds of different chemical classes listed in the Stockholm Convention on POPs, which aims to protect the environment and human health [...

Effect of Organic and Mineral Soil Fractions on Sorption Behaviour of Chlorophenol and Triazine Micropollutants

This article compares the sorption behaviour of 2,4,6-trichlorophenol, 2,3,4,6-tetrachlorophenol, pentachlorophenol, chlorotriazine atrazine, methylthiotriazine ametryn, methoxytriazine atratone, hydroxyatrazine, and didelakylated atrazine in a topsoil and an aquifer sediment before and after removal of sorbent organic matter and in humic acid. Freundlich isotherm coeffi cients Kf and 1/n and free energy change (∆G°) were calculated for all compounds in all sorbents. According to sorbent pH values, chlorophenolate anions and uncharged triazine species dominated in all sorption experiments with topsoil and aquifer sediment. In experiments with humic acid, chlorophenols, atrazine, and didealkylated atrazine existed almost completely as neutral species, whereas protonated species dominated for hydroxyatrazine, atratone, and ametryn. In addition to a hydrophobic partition, sorption of all compounds in native soil and sediment sorbents includes specifi c, more polar interactions, which greatly depend on sorbate acidity/ basicity, specifi c properties of the sorbent organic matter and of mineral surface, as well as on the system pH. A signifi cantly greater sorption intensity of all compounds in “organic-free” than in the native aquifer sediment confi rmed the importance and possible dominance of mineral surface in the sorption process. Sorption intensity of chlorophenol and triazine compounds in humic acid was closely related to compound hydrophobicity. Greater sorption of almost completely protonated hydroxyatrazine than of the more hydropohobic but uncharged atrazine indicated different humic acid reaction sites for two compounds and consequently different sorption mechanisms.Uspoređena je sorpcija 2,4,6-triklorfenola, 2,3,4,6-tetraklorfenola i pentaklorfenola te različito supstituiranih triazinskih spojeva - klortriazina atrazina, metiltiotriazina ametrina, metoksitriazina atratona i razgradnih produkata atrazina hidroksiatrazina i didealkiliranog atrazina – u površinskom tlu i sedimentu vodonosnika prije i nakon uklanjanja organske tvari te u huminskoj kiselini. Izračunani su koefi cijenti Freundlichove izoterme Kf i 1/n te izmjena slobodne energije (∆G°) za sve spojeve i sorbense. U skladu s pH-vrijednostima sorbensa u svim su sorpcijskim pokusima s nativnim tlom i sedimentom prevladavali klorfenolatni anioni i neutralni triazinski spojevi. U pokusima s huminskom kiselinom klorfenoli, atrazin i didealkilirani atrazin postojali su kao neutralne vrste, dok su hidroksiatrazin, atraton i ametrin bili većim dijelom protonirani. Sorpcija svih spojeva u prirodnom tlu i sedimentu uključuje uz hidrofobnu particiju i specifi čne polarnije interakcije ovisne o kiselosti/bazičnosti sorbata, specifi čnim svojstvima organske tvari i mineralne površine sorbensa te o pH-vrijednosti sustava. Intenzitet sorpcije svih spojeva u sedimentu iz kojeg je uklonjena organska tvar bio je značajno veći od sorpcije u prirodnom sedimentu, što potvrđuje važnost i moguću dominantnu ulogu mineralne površine u sorpcijskom procesu. Intenzitet sorpcije klorfenola te klortriazina, metiltiotriazina i metoksitriazina u huminskoj kiselini korelirao je s hidrofobnosti spojeva. Veća sorpcija gotovo potpuno protoniranog hidroksiatrazina od hidrofobnijeg, ali neutralnog atrazina upućuje na različita reakcijska mjesta za ova dva spoja, a time i na različite mehanizme sorpcije u huminskoj kiselini