Türkiye kıyılarında tersane ve marina faaliyetlerinden kaynaklanan organik kirletici seviyelerinin pasif örnekleyiciler yardımıyla belirlenmesi
Determination of organic pollutant levels in shipyard and marina waters by passive sampling
Yazar: ATİLLA YILMAZ
Danışman: PROF. DR. OYA OKAY ; DOÇ. DR. BARIŞ BARLAS
İstanbul Teknik Üniversitesi / Fen Bilimleri Enstitüsü / Gemi ve Deniz Teknoloji Mühendisliği Ana Bilim Dalı
Derece: Yüksek Lisans, 2014
Konu: Deniz Bilimleri = Marine Science ; Çevre Mühendisliği = Environmental Engineering

Özet:
Ağır sanayinin önemli bir parçası olan tersaneler ve yatlara barındırma hizmeti sağlayan marinaların deniz kirliliğine olan etkilerinin incelenmesi doğal yaşam ve insan sağlığı açısından büyük önem taşımaktadır. Bu çalışma kapsamında; tersane ve marinalarda organik kirleticiler olarak polisiklik aromatik hidrokarbonlar (PAH), poliklorlu bifeniller (PKB) ve organoklorlu pestisitler (OKP) incelenmiştir. Organik kirleticilerin sudaki düşük çözünürlükleri nedeniyle, çoğu analitik yöntemle sudaki konsantrasyonları belirlenememektedir. Pasif örnekleyiciler ise, su ortamında belirli bir süre boyunca suda çözünmüş olarak bulunan kirletici moleküllerini örnekleyerek, zamana yayılı ortalama bir değer vermektedir. Bu çalışmada, pasif örnekleyici olarak, petrol dökülmelerini temizlemek amacıyla geliştirilen ve bu çalışmada ilk kez pasif örnekleyici olarak kullanılan bütil kauçuk (BK) sorbent ve yarı geçirgen membran örnekleyiciler (SPMD) kullanılmıştır.
Çalışma kapsamında; tersane ve marinalarda organik kirletici seviyelerinin belirlenmesi için Marmara ve Akdeniz bölgelerinde bulunan iki farklı marinaya ve Tuzla tersaneler bölgesine, 30 gün süreyle pasif örnekleyiciler yerleştirilmiştir. Bunlara ek olarak, yapılacak çalışmalarda referans olarak kullanılmak üzere, Saros Körfezi, Çanakkale Boğazı ve Tuzla'da bulunan İTÜ Denizcilik Fakültesi'nde farklı istasyonlar belirlenip çalışmalar gerçekleştirilmiştir.
Örnekleme süresi sonunda toplanan pasif örnekleyiciler, Almanya'nın Münih kentinde bulunan Helmholtz Zentrum laboratuvarlarında gaz kromatografisi-kütle spektrometresi sistemiyle analiz edilmiştir. SPMD'ler ile örneklenen toplam PAH konsantrasyonları 37 - 3338 ng/g SPMD, toplam PKB konsantrasyonları 97 - 4247 pg/g SPMD ve toplam OKP konsantrasyonları 2915 - 13673 pg/g SPMD aralığında saptanmıştır. Bütil kauçuk sorbentler ile örneklenen toplam PAH konsantrasyonları 19,7 - 2083 ng/g BK sorbent, toplam PKB konsantrasyonları 638 - 8306 pg/g BK sorbent ve toplam OKP konsantrasyonları 2496 - 17479 pg/g BK sorbent aralığında ölçülmüştür.
SPMD'lerde saptanmak istenen organik bileşiklerin izotopları olan performans referans bileşikleri (PRB) kullanılmaktadır. Bu bileşikler (naftalin-13C6, asenaftilen-13C6, asenaften-13C6, floren-13C6, fenantren-13C6, antrasen-13C6, floranten-13C6, piren-13C3, benzo(a)antrasen-13C6, krisen-13C6, benzo(b)floranten-13C6, benzo(k)floranten-13C6, benzo(a)piren-13C4, indeno(1,2,3-cd)piren-13C6, benzo(ghi)perilen-13C12, dibenzo(a,h)antrasen-13C6) SPMD'lere üretim aşamasında eklenmektedir. Örnekleme süresi sonunda SPMD içerisinde kalan PRB miktarları kullanılarak, organik bileşiklerin sudaki konsantrasyonları hesaplanabilmektedir. Ayrıca, performans referans bileşikleri yardımıyla örnekleyici ve ortamda bulunan organik bileşik moleküllerinin denge konumuna gelip gelmediği hakkında bilgi edinebilmektedir.
SPMD'ler ile yapılan örneklemelerden elde edilen analiz sonuçları, 80/20 ve NLS (Nonlinear Least Squares) olmak üzere iki farklı yöntem kullanılarak değerlendirilmiş ve kirleticilerin deniz suyundaki konsantrasyonları tahmin edilmiştir. NLS yöntemiyle hesaplanan sudaki toplam PAH konsantrasyonları 0,86 - 184 ng/L SPMD, toplam PKB konsantrasyonları 1,7 - 186 pg/L ve toplam OKP konsantrasyonları 98 - 848 pg/L değerleri arasında değişmektedir. 80/20 yöntemiyle yapılan hesaplamalarda, NLS yöntemiyle hesaplanan konsantrasyonlara yakın değerler elde edildiği görülmüştür.
İki farklı pasif örnekleyici ile elde edilen örnekleme verileri karşılaştırıldığında, BK sorbentlerin çoğu PKB ve OKP bileşiklerini ve yüksek oktanol-su ayrışım katsayısı (KOW) değerine sahip PAH bileşiklerini SPMD'lere göre daha iyi örneklediği gözlemlenmiştir.
SPMD örnekleme sonuçları kullanılarak marinalardaki organik kirletici seviyeleri üzerine sayısal bir model oluşturulmuştur. Yatların ve küçük teknelerin marina sularında organik kirletici konsantrasyonlarına etkisini belirlemek için oluşturulan sayısal model sonuçlarının, SPMD örnekleme verileriyle hesaplanan sudaki kirletici konsantrasyonlarıyla uyumlu olduğu görülmüştür. Girdi parametreleri arttırılarak modelin geliştirilmesi ve daha fazla noktada uygulanarak modelin tekrarlanabilirliğinin doğrulanması gerektiği düşünülmektedir.
Yapılan örnekleme çalışmaları ve analizler sonucunda, gemi yapım ve onarım faaliyetlerinin sudaki organik kirletici konsantrasyonlarını yüksek oranda arttırdığı sonucuna varılmıştır. Elde edilen veriler, marinalar için bu konuda kesin bir yargıya varılamayacağını göstermiştir. Buna rağmen, yine de marinaların mercek altına alınması gerektiği düşünülmektedir. Deniz ortamıyla iç içe olan tersane ve marina gibi işletmelerde, yetkili resmi kurumlar tarafından düzenli olarak incelemeler ve ölçümler yapılmalıdır. Bu çalışmada elde edilen verilerin, gelecekte bu bölgelerde yapılacak bilimsel araştırmalarda ve risk değerlendirme çalışmalarında bir zemin oluşturacağı düşünülmektedir.

Abstract:
Shipyards, which both construction and repair acitivites are performed, are indispensable elements of heavy industry. Marinas provide various services including shelter, repair and supplies for yachts and small leisure crafts, and they have non-negligible contribution to economy. For the safety and future of the natural life and human health, it is essential to observe the effects of shipyards and marinas to marine pollution.
In this study, concentration of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were determined in shipyard and marina waters. Due to their hydrophobic structure, solubility of the organic pollutants are very low in water. Therefore, the concentrations of the organic pollutants in water can not be accurately analysed with known analytical methods. In order to overcome this problem, passive samplers are used for sampling of the organic pollutants. Dissolved pollutant molecules are accumulated in the structure of passive samplers during a certain period of time. Thus, those samplers give a time-integrated average concentrations of the accumulated organic compounds.
Lipid containing semi permeable membrane devices (SPMDs) and butyl rubber (BR) sorbents were used as passive samplers. This study involves the first usage of butyl rubber sorbent as a passive sampler, which was actually designed and developed as an oil spill clean-up device by Istanbul Technical University, Department of Chemistry. Butyl rubber sorbents are highly hydrophobic, reusable and durable. Semi permeable membrane devices contain triolein in sealed low density polyethylene tube and they are widely used in the monitoring of organic compounds in air, water and soil matrices. Semi permeable membrane devices are designed to mimic the fatty tissues of the organisms and they also provide data for bioavailable concentrations of the pollutants.
For the determination of the levels of organic pollutants in shipyard and marine waters; passive samplers were deployed to two different marinas in Marmara and Mediterranean region of Turkey; and Tuzla Shipbuilding Zone where several shipyards are located. The deployment period was 30 days and the sampling was performed at spring of 2012.
Additionally, further sampling was performed at Saros Bay, Dardanelles Strait and ITU Maritime Faculty in Tuzla, Istanbul. These regions were considered as unpolluted and considered as reference sampling stations to observe the effects of shipyards and marinas to marine pollution.
Semi permeable membrane devices and butyl rubber sorbents were placed in special stainless steel cages; fixed by ropes to the sea bottom and supported by buoys to help the cages hung in the water column. After 30 days, passive samplers were retrieved, put into small vials and transferred to the laboratory immediately after collection. The samples were stored at -20° C until the analyses were performed.
The samples were analysed in the laboratories of Helmholtz Zentrum München, Germany. SPMDs were extracted in cyclohexane with orbital shaker and BR sorbents were analysed by high resolution gas chromatography coupled with a high resolution mass spectrometry system in selected ion monitoring mode. For the quantification, 13C-isotope dilution method was used. Site control samples and laboratory blanks were used as quality control samples.
According to the data obtained by analyses, the concentrations of organic pollutants sampled by SPMDs ranged from 37 - 3338 ng/g SPMD for total PAH compounds, 97 - 4247 pg/g SPMD for total PCB compounds and 2915 - 13673 pg/g SPMD for total OCP compounds for all sampling stations. For BR sorbents, these concentrations varied between 19,7 – 2083 ng/g BR sorbent for total PAH compounds, 638 - 8306 pg/g BR sorbent for total PCB compounds and 2496 - 17479 pg/g BR sorbent for total OCP compounds.
The sampling results of semi permeable membrane devices showed that high concentrations of PAH compounds were present at shipyard sampling stations and at the marina located in the coastal area of Istanbul (Marina 1). PAH concentrations of the shipyard stations were compared to the related reference station (ITU Maritime Faculty - Tuzla). The results showed that the high concentrations of PAHs are related with shipbuilding and repair activities. This was also supported by the pyrolytic origin of the detected PAH compounds in shipyard area. Previous investigations showed that high PAH concentrations were detected in waters of the region which Marina 1 is located. Therefore, it would not be correct to associate the measured high PAH concentrations only with the marina activities.
The calculations pointed out that the PAH concentrations found in the Marina 1 has pyrolytic origin. Thus, measured concentrations of PAHs may be related to emissions resulted from both marine and land transportation and/or home heating in the nearby residential area. Relatively low concentrations of PAH compounds were detected in Marina 2 located in Bodrum, Muğla and the origin of these compounds were found to be petrogenic. It is suggested that the measured PAH concentrations may be the result of fuel and bilge waters spills from of the boats in the marina.
PCB concentrations acquired by SPMDs were observed at high levels at shipyard stations and Marina 1. Very low PCB concentrations were detected in Marina 2 stations. Since PCBs were formerly used in marine paints and electric equipment, the source of the high PCB concentrations at shipyards were thought to be mainly results of paint removal and repairment activities in shipyards. Detected high PCB concentrations in Marina 1 were found to be related to high residential population around the marina region. When low PCB concentrations found in Marina 2 stations are considered, it cannot be stated that marina activities increases PCB concentration in water.
The highest concentrations of OCP compounds were observed in Marina 1 and shipyard sampling stations. OCP concentrations at shipyards were considerably high when compared to related reference sampling station. Paint removal and application of insecticides for ships would be a possible cause for this situation. High DDT ratios found in shipyard stations also support this hypothesis. Relatively low concentrations were found at Marina 2 compared to the other sampling stations.
Data obtained from sampling by SPMDs were evaluated by two different back-calculation methods (80/20 and Nonlinear Least Squares methods) in order to estimate the water concentration of the organic pollutants. Performance reference compounds (PRCs ), which are isotopes of the analyte compounds (naphthalene-13C6, acenaphthylene-13C6, acenaphthene-13C6, fluorene-13C6, phenanthrene-13C6, anthracene-13C6, fluoranthene-13C6, pyrene-13C3, benzo (a) anthracene- 13C6, chrysene-13C6, benzo (b) fluoranthene-13C6, benzo (k) fluoranthene-13C6, benzo (a) pyrene-13C4, indeno (1,2,3-cd) pyrene-13C6, benzo (ghi) perylene-13C12, dibenzo (a,h) anthracene-13C6) are spiked into SPMDs during the production period. PRCs are also analysed in order to determine whether the sampler and the media is in the uptake or equilibrium state for a particular compound. These methods use the retained performance reference compound levels, considering the exchange kinetics of the compounds, for the calculation of water concentration of organic pollutants. The main distinction between two applied calculation methods is that nonlinear least squares (NLS) method uses all of the retained PRC data, whereas in 80/20 method, only one selected PRC is used. Hence, the concentrations calculated by NLS method are considered to be more accurate compared to 80/20 method.
The estimated water concentrations of the organic pollutants by NLS method ranged between 0,86 - 184 ng/L for total PAH, 1,7 - 186 pg/L for total PCB and 98 - 848 pg/L for total OCP. Those concentrations calculated by 80/20 method were found similar that calculated by NLS method. Estimated water concentrations were evaluated with respect to European Union environmental quality standarts where limit concentrations for hazardous chemicals are defined. It was found that most of the detected concentrations are below the limits although some of the compounds in shipbuilding zone were above the limits.
In this study, the sampling performances of the passive samplers were also compared. SPMD and BR sorbent sampling results were found to be in the same order of magnitude. It was observed that BR sorbents accumulates most of the PCB and OCP compounds and PAHs (with high octanol-water partition coefficient-KOW) more efficiently compared to SPMDs. It was suggested that this situation may be related to higher hydrophobic nature of the BR sorbents.
In addition, a numerical model was established for marinas to estimate the contribution of boats in to organic pollutant levels. The numerical model was based on the calculated water concentrations by using semi permeable membrane devices and capacities of a particular marina. The model was applied to two seperate parts in the second marina. It was observed that the model output were highly coherent with the water concentrations calculated by NLS method.
As a conclusion, it was found that construction and repair activities in shipyards increases the levels of organic pollutants in water. Obtained sampling data show that a certain judgement about the contribution of marinas to organic pollutant levels can not be clearly stated. Nevertheless, shipyard and marinas are always potential sources for the marine pollution and should be regularly investigated. Regulations should be defined and specific guidelines for shipyards and marinas should be prepared in order to keep the marine pollution under control. This study provides a baseline data for risk assessment evaluation and future scientific research in shipyards and marinas.