The acidity of water can condition the toxicity of chemicals in water. The work developed by a research team from the Universities of Tübingen and Athens, points in this line. As the researchers have shown, the toxicity of the chemical derivatives present in the water of rivers and lakes can be altered by the acidity of the water itself. For this study, 24 substances were used, most of which are used in the pharmaceutical industry.

Toxicity predictions

The research designed a model that allows toxicity predictions to be made. A substantial part of the active ingredients of drugs is excreted by the human body after ingestion. These substances are designed to be broken down once taken, so a large part can be excreted and reach the wastewater through the stool. In this way, the drugs reach the environment.

There are drugs composed of substances that are ionizable molecules. Therefore, they can be in both neutral and electrically charged form. The fluid can have significantly varying acid-base ratios, e.g. pH. Professor Heinz Köhler, a member of the study, points out that these variables influence the absorption of substances into the cells of a living organism.

The fluid can have significantly varying acid-base ratios.

Testing phase

A fish was chosen as the experimental organism. During the testing phase, zebrafish eggs were exposed to the chemicals chosen for the study. For each situation, the LC50 parameter was established, which is associated with the concentration of contaminants that causes the death of every second fish embryo. As part of the research, the toxicity of the chemicals was evaluated at four different pHs, carrying out more than 1200 tests.

The researchers observed wide variations. Köhler notes that for substances such as diclofenac, the beta-blocker propranolol and fluoxetine, the LC50 value showed considerable changes. After the test phase, a more than 1,000-fold change was observed between pH 5 and pH 9.

In the results, the researchers observed wide variations

In the testing phase, the most complicated scenarios were configured. In this way, with the release of the pharmaceutical derivatives into the water, it was foreseeable that they would not harm living organisms even under the most adverse conditions. It was observed that, in general terms, the substances were more toxic when they were uncharged than in their ionized form.

Different scenarios to simulate possible effects

Different scenarios were configured. For this purpose, the researchers developed different approaches according to different hypotheses about pharmaceuticals that manage to penetrate the cell membrane and the damage they can cause.

Three levels of magnitude were observed. In order to simulate toxicity according to different pH levels of ambient water, a comparison of six mathematical models was carried out. As stated by Köhler, the model that offered a reliable formula to emulate the possible effects on organisms according to three magnitude levels was chosen.

A model was chosen that offered a formula to simulate possible effects according to three magnitude levels

Conclusión

La investigación mejora el conocimiento para realizar mejores predicciones de toxicidad. Como apuntan los investigadores, se ha incrementado la comprensión sobre la toxicidad que pueden representar las sustancias estudiadas. Además, los resultados obtenidos pueden ser de aplicación para distintos campos que tengan presentes valores de referencia. 

Related news

Sensores para la detección temprana de toxinas en el agua Bluegold

Investigadores diseñan sensores que permiten detectar toxinas en el agua

Investigadores de la Universidad de Cincinatti diseñan un sensor que detecta toxinas del agua antes de que acceda a la planta de tratamiento

bacterias resistentes a los antibióticos- Blue gold

Desinfección de agua contra las bacterias resistentes a antibióticos

Una investigación, analiza la capacidad de desinfección de distintos desinfectantes contra las bacterias resistentes a los antibióticos

Análisis-de-aguas-residuales-para-medir-la-exposición-a-pesticidas-BlueGold

Detectar la ingesta de pesticidas a través de las aguas residuales

Una investigación analiza la ingesta de pesticidas en una población residual analizando sus aguas residuales

error: Contenido esta protegido