Darija Vukić Lušić

The responses of the hepatosomatic index (HSI), 7-ethoxyresorufin-O-deethylase (EROD) activity and glutathione-S-transferase (GST) activity in sea bass (Dicentrarchus labrax, Linnaeus 1758) caged at a polluted site: implications for their use in environmental risk assessment

The present study investigates the response of three hepatic biomarkers in adult sea bass (Dicentrarchus labrax, Linnaeus 1758) caged at a wastewater outlet of an oil refinery with fish caged at a pristine site used as controls. The biomarkers that were investigated were the hepatosomatic index (HSI), 7-ethoxyresorufin-O-deethylase (EROD) activity and glutathione-S-transferase (GST) activity. In addition, we have measured the levels of polycyclic aromatic hydrocarbons (PAHs) and selected heavy metals (lead, cadmium, mercury, copper and zinc) in sediment samples at the polluted site. Although the polluted site had high environmental levels of PAHs and heavy metals, there was no difference in hepatic EROD activity and HSI between fish caged at the polluted site and controls. On the other hand, GST activity was significantly lower in fish caged at the polluted site compared to controls. Our results point out that the studied biomarkers have limited use in environmental risk assessment studies, at least when caged adult sea bass is used as the sentinel species and complex toxicant mixtures are involved.

Microbiological and chemical indicators of water quality in indoor hotel swimming pools before and after training of swimming pool operators.

The present study was undertaken in order to determine the quality of indoor pool waters in hotels along the Croatian coast. We wanted to assess the risks of exposure to microbial and chemical contaminants and find out if training pool operators to use a quality assurance system, that we developed, influenced hygienic conditions and water quality in swimming pools or not. The samples were analysed for free chlorine, pH and several microbiological indicators according to standard laboratory methodologies. Of 1,329 samples tested, 276 were found to be unacceptable either by chemical (148) or microbiological parameters (128). After training, the proportion of unacceptable samples dropped by 23.5%, mostly according to the free chlorine values. According to our results, most of the microbiologically unacceptable samples had chlorine levels within the recommended range but their pH values were too high. A free chlorine level below 0.2 mg/L was found in 106 (82.8%) microbiologically unacceptable samples suggesting the need for maintaining the lower limit at least above 0.2 mg/L in order to reduce microbial risks to a more acceptable level. This measure combined with training of pool operators might result in reduced health risks in pool waters.

Evaluation of equivalence between different methods for enumeration of fecal indicator bacteria before and after adoption of the new Bathing Water Directive and risk assessment of pollution

The quality of bathing water is of considerable public importance due to the possibility of fecal contamination. In 2009, Croatia implemented the new European Bathing Water Directive (BWD, 2006/7/EC) establishing stricter microbiological standards for new parameters with new reference methods. This study aims to evaluate the equivalence of different methods according to the old and revised BWD and to provide the possibility of data comparison. Furthermore, the directive requires the establishment of the bathing water profile (BWP) for pollution risk assessment. The estimation of consistency of pollution risk assessment with obtained microbiological results was also performed. Six marine beaches of the Municipality of Rijeka (Croatia) were examined during the 2009 season. Statistical analysis showed equivalence between determination methods for fecal contamination indicators. Based on the current water classification results, the need for correction of estimated pollution risks and recommendations for inclusion of historical microbiological data during BWP enactment was noticed.

Exposure to Phtalates and Their Presence in Alcoholic Beverages

Ftalati su esteri ftalne kiseline i alifatskih alkohola koji se dodaju u plastične mase da bi se poboljšala njihova mekoća, savitljivost i rastezljivost. Zbog svojih fizičko-kemijskih svojstava ftalati su vrlo mobilni i lako migriraju iz plastičnih proizvoda u prostor koji ih okružuje, pa tako dospijevaju u okoliš te su stoga opasni za čovjeka. U radu su ukratko opisana svojstva i raspodjela ftalata u okolišu, toksični učinci na ljudsko zdravlje te zakonska regulativa vezana uz maksimalno dopuštene koncentracije ftalata u vodi za piće i u proizvodima namijenjenima dojenčadi, kao i dopušteni dnevni unos u ljudski organizam. Posebna pažnja posvećena je metodama određivanja ftalata u alkoholnim pićima te razinama ftalata s osvrtom na njihovu pojavnost i koncentracije u šljivovici koja se proizvodi u Hrvatskoj. Obuhvaćena je i tematika vezana za ftalate u denaturiranom alkoholu i neregistriranom alkoholu koji se ilegalno stavlja na tržište. U zaključku su navedene smjernice za učinkoviti nadzor nad putovima izloženosti ljudi ftalatima. Summary Phthalates are phthalic acid and aliphatic alcohol esters used as additives to plastic in order to improve its softness, flexibility, and elongation. Phthalates are highly mobile and migrate easily from plastic products into the environment due to their physical and chemical properties. This study briefly describes the characteristics and distribution of phthalates in the environment, their toxic effects on human health, the legislation regarding the maximum allowed concentration of phthalates in drinking water and products intended for infants, as well as the tolerable daily intake. Special attention is given to the methods of determining phthalates and their levels in alcoholic beverages, with an overview of phthalate occurrences and concentrations in plum brandy made in Croatia. A segment on denatured alcohol and illegally marketed alcohol is also included, as well as guidelines for the effective monitoring of the routes of human exposure to phthalates.

Temporal variations analyses and predictive modeling of microbiological seawater quality

Bathing water quality is a major public health issue, especially for tourism-oriented regions. Currently used methods within EU allow at least a 2.2 day period for obtaining the analytical results, making outdated the information forwarded to the public. Obtained results and beach assessment are influenced by the temporal and spatial characteristics of sample collection, and numerous environmental parameters, as well as by differences of official water standards. This paper examines the temporal variation of microbiological parameters during the day, as well as the influence of the sampling hour, on decision processes in the management of the beach. Apart from the fecal indicators stipulated by the EU Bathing Water Directive (E. coli and enterococci), additional fecal (C. perfringens) and non-fecal (S. aureus and P. aeriginosa) parameters were analyzed. Moreover, the effects of applying different evaluation criteria (national, EU and U.S. EPA) to beach ranking were studied, and the most common reasons for exceeding water-quality standards were investigated. In order to upgrade routine monitoring, a predictive statistical model was developed. The highest concentrations of fecal indicators were recorded early in the morning (6 AM) due to the lack of solar radiation during the night period. When compared to enterococci, E. coli criteria appears to be more stringent for the detection of fecal pollution. In comparison to EU and U.S. EPA criteria, Croatian national evaluation criteria provide stricter public health standards. Solar radiation and precipitation were the predominant environmental parameters affecting beach water quality, and these parameters were included in the predictive model setup. Predictive models revealed great potential for the monitoring of recreational water bodies, and with further development can become a useful tool for the improvement of public health protection.

Escherichia coli in marine water: Comparison of methods for the assessment of recreational bathing water samples

Bathing Water Directive (2006/7/EC) specifies two reference methods for Escherichia coli detection: ISO 9308-1 and 9308-3. The revised ISO 9308-1 is recommended only for waters with a low bacterial background flora. Considering the extended time needed for analysis and, generally, the lack of experience in using ISO 9308-3 in the Mediterranean, the suitability of ISO 9308-1 for the examination of E. coli in bathing water was evaluated. The present study was aimed at a comparison of data obtained by the reference method in seawater samples (110 beaches, N=477) with data received from six alternative methods. Results show that recently used TSA/TBA method may overestimate E. coli numbers in marine waters. The temperature modified ISO 9308-1 (44°C) did not significantly alter the results, but outperformed the antibiotic supplemented agar at reducing non-E. coli bacteria on the plates, allowing the use of the respective method for monitoring coastal water.

Status of faecal pollution in ports: A basin-wide investigation in the Adriatic Sea

Ports are subject to a variety of anthropogenic impacts, and there is mounting evidence of faecal contamination through several routes. Yet, little is known about pollution in ports by faecal indicator bacteria (FIB). FIB spatio-temporal dynamics were assessed in 12 ports of the Adriatic Sea, a semi-enclosed basin under strong anthropogenic pressure, and their relationships with environmental variables were explored to gain insight into pollution sources. FIB were abundant in ports, often more so than in adjacent areas; their abundance patterns were related to salinity, oxygen, and nutrient levels. In addition, a molecular method, quantitative (q)PCR, was used to quantify FIB. qPCR enabled faster FIB determination and water quality monitoring that culture-based methods. These data provide robust baseline evidence of faecal contamination in ports and can be used to improve the management of routine port activities (dredging and ballast water exchange), having potential to spread pathogens in the sea.

A baseline study of the metallothioneins content in digestive gland of the Norway lobster Nephrops norvegicus from Northern Adriatic Sea: Body size, season, gender and metal specific variability

Metallothioneins content was investigated in digestive gland of two wild-caught Norway lobster Nephrops norvegicus populations from the Northern Adriatic Sea, in relation to body size, season and gender. Concomitant accumulation of cadmium, mercury, arsenic, lead, chromium and manganese, reactive oxygen species concentration and energy reserves in digestive gland were also assessed. While differences between genders were not recorded, metallothioneins content seasonal trends were affected by body size. Most of parameters displayed inconsistent trends across sampling sites. Significant correlation between metallothioneins content and cadmium, arsenic and mercury concentrations was recorded only for larger lobsters. A negative correlation of reactive oxygen species concentration and metallothioneins content was observed for small, but not large lobsters. Energy reserves, in particular lipids, could considerably influence biochemical and chemical parameters variations. The present results constitute the essential baseline for future studies aimed at evaluating the N. norvegicus health in relation to metal contamination of coastal sediments.

Zdravstvena ispravnost vode za piće u Gorskom kotaru u petogodišnjem razdoblju od 2011. do 2015.

Cilj: Osiguranje zdravstveno ispravne vode osnovna je potreba svakog covjeka. S obzirom na dugogodisnje mikrobiolosko oneciscenje u vodoopskrbno