Presence of active pharmaceutical ingredients in wastewater and many bodies of water reaches concentration unsafe for the environment

Studies of the presence of active pharmaceutical ingredients in wastewater and in the rivers and other bodies of water in Latvia and Lithuania have revealed that in many places the concentration of these substances either is close to or exceeds the level which is considered to be safe for environment. According to the results of chemical analysis, majority of the studied water samples are dominated by active ingredients contained by anti-inflammatory drugs and painkillers.

Within the EU project “Pharmaceuticals in wastewaters–levels, impacts and reduction”, the Latvian and Lithuanian scientists are studying wastewater pollution with active pharmaceutical ingredients with the underlying goal of searching for solutions for reducing this pollution.

“I was convinced that active pharmaceutical ingredients will be found in both wastewater and rivers, which they enter; but what is most surprising is that the amount of these substances is approaching levels that are unsafe for the environment or even exceeds them,” says the project manager researcher Ieva Putna-Nīmane from Daugavpils University Agency “Latvian Institute of Aquatic Ecology”. Although she admits that human health largely depends on medicine, she also reminds that “we should, however, remember that people also are significantly affected by the health of the environment.”

During the last summer and winter, more than 60 wastewater samples were collected in Latvia and Lithuania from 16 wastewater treatment plants and 16 bodies of water selected by the scientists. The samples were analysed at the Marine Research Institute, Klaipėda University, to determine the concentrations of 25 active pharmaceutical ingredients. As pointed out by Klaipeda University Doctor Sergey Suzdalev, results of chemical analysis do not surprise scientists. “Wastewater flows in most of the studied bodies of water are dominated by analgesic and anti-inflammatory active ingredients, like ibuprofen, diclofenac, paracetamol,” explains Suzdalev. “These medications are used extensively in both Latvia and Lithuania, so the substances contained by them end up in large quantities in wastewater treatment plants and water bodies. What is worrying is that, for example, the presence of diclofenac in many places exceeds the annual environmental quality standard value recommended by the European Commission, which is 10 ng per litre,” continues Sergey Suzdalev. Results of previous researches suggest of similar situation also in other EU countries.

The project partners, which include the State Agency of Medicines of the Republic of Latvia and the State Medicines Control Agency under the Ministry of Health of the Republic of Lithuania, also collect data on the medications sold in both countries from 2018 until 2020. According to these results, the drug consumption patterns are similar in both neighbour countries. For example, out of the selected 25 active pharmaceutical ingredients the one sold most is metformin, which is contained by drugs used to treat metabolic diseases. During a period of three years, more than 100 thousand kilograms of this substance have been sold in each country. The data on the sale of drugs was compared with the concentrations of substances in untreated wastewater. And, as expected, no direct correlation was found since concentrations are related to the nature of the particular substance.

“I want to thank all wastewater treatment plants and the Latvian Water and Wastewater Works Association for their support in this research and cooperation. Although wastewater treatment plants have not been designed to remove active pharmaceutical ingredients from wastewater, our study suggests that they manage to reduce the pollution by 33–80%,” informs the researcher Ieva Putna-Nīmane.