Originally this study was designed to focus on mercury (Hg), lead (Pb) and Cadmium (Cd), three heavy metals that are of primary concern in European marine environments because of their toxicity and ability to bio-accumulate/bio-concentrate in marine organisms/humans. During the first phase of the project I secured access to data from a 2011 paper on heavy metal concentration gradient along the proposed focus area, the industrial Klaipeda port. I also established a direct contact with the Coastal Water Quality Model (CWQ model) developers at Stanford University. I conducted an initial calibration of the CWQ model specific to Hg, Pb, Cd and Klaipeda coastal water, and based on the real-world heavy metal industrial discharge data available, the CWQ model was used to generate heavy metal concentration map. The model output was compared with the real-life heavy metal concentration data from 2006-2008 to ensure its accuracy in reflecting local marine physical transport and biogeochemical processes; the model was adjusted/calibrated until the model's generated values reflected the available field data.
However, during initial investigations, heavy metals were found to be inappropriate for this study as most heavy metals originate from the non-point sources (e.g. historical accumulation of heavy metals in coastal sludge, commercial activities of the port or its leakage from old ships), making the application of the proposed technological solution almost impossible.
As such, this study was refocused towards pharmaceuticals and other micropollutants. It is widely considered that most of these enter the environment via our wastewater treatment plants (WWTPs), and they present significant potential risk to the environment and human health (e.g. increased antimicrobial resistance). In December 2019 an international study (MORPHEUS) funded by the EC was completed by Kristianstad University, University of Rostock, Gdansk University of Technology and Klaipeda University, with a focus on four key field sites of Southern Baltic: Skane (Sweden), Mecklenburg (Germany), Klaipeda (Lithuania) and Pomerania (Poland).
During the second phase of the project the following work was conducted: (1) established the partnership with the key scientists of MORPHEUS project (2) evaluated and selected 14 drugs from five classes: antiinfectives for systemic use; muscolo-skeleton system; nervous system; genito urinary system and sex hormones; cardiovascular system; data on concentration of the drugs along the selected study sites was available based on the MORPHEUS project (3) conducted an initial calibration of the CWQ model specific to the selected drugs and targeted coastal waters in the same selected test sites as the MORPHEUS project; (4) Based on the real-world available drug discharge data, the CWQ model was used to generate pharmaceutical concentration map along the targeted coastal waters; the model output was compared with the real-world drug concentration data from the same collection locations to ensure the model’s accuracy.
An initial calibration (designed for pharmaceutical drugs) of the CAESAR Bioconcentration and KABAM Bioaccumulation Models was conducted. Bioconcentration factor (BCF) describes the likelihood of a chemical concentrating in organisms, when the compound is present in the environment. It is required for regulatory purposes, for example within the REACH and GHS regulations. Bioaccumulation factor (BAF) is similar to BCF but more general term referring to uptake and accumulation of a substance from all sources combined (water, food, etc.) and it is especially important in the scientific evaluation of risks that chemicals may pose to humans and the environment. Since scientific literature data on BAF is less available than on BCF, utilizing both in this study provides better accuracy in results interpretation. Pharmaceutical drugs have a high tendency to bioconcentrate and bioaccumulate in aquatic organisms, including commercial fish, thus creating a substantial health risks to humans who consume the fish. As a result, BAF and BCF could be used as a valid indicators of pharmaceutical drugs' negative effect on fish (and eventually human health).
