Contaminated soils, health hazard

• April 25, 2024

Soils contaminated with hydrocarbons represent a risk to human health, hence the importance of making a diagnosis of the area before locating population centers in areas impacted with these compounds.

In Mexico, this pollution occurs due to clandestine gasoline or diesel, therefore, this type of event must be prevented and the affected areas must be remedied. To avoid these accidents it is advisable to have a good management of the operating practices in the extraction, distribution and storage of hydrocarbons.

The Institute of Engineering of the UNAM He made risk maps for human health of a contaminated site located in northern Mexico, which has an area of ​​about 900 hectares.

These maps were obtained from satellite images, geographic information systems and sampling at the site. The purpose of this project is to count, quickly and economically, with information that allows to know if it is feasible to authorize the settlement of a population or not.

The specialist in environmental engineering, Rosa María Flores Serrano , and their team, after analyzing images and samples, confirmed the presence of heavy fraction hydrocarbons in those points that were selected; the risk was calculated.

The Official Mexican Standard NOM-138-SEMARNAT / SS-2003 defines three fractions of hydrocarbons: light, medium and heavy. Each of these are mixtures of several organic compounds. For example, the heavy fraction is hydrocarbons with chains of more than 18 carbons, which may represent a risk to human health.

In this project, the type of risk it measures is considered within the anthropogenic ones, where the stress producing agent is the pollutant, that is, the toxic substances contained in soil, water or air, with which the population comes into contact. These substances are divided into two types: carcinogenic and non-carcinogenic.

The risk value that they estimated in this project was measured as a hazard ratio because non-carcinogenic (systemic) effects were evaluated. It should be noted that some of the hydrocarbons that are in the mixture of heavy fraction can cause neurological damage in kidney, liver and lungs.

The hazard ratio results from dividing an exposure dose (which is calculated based on the exposure conditions in the population and the concentrations in the soil), between a reference dose (with which no adverse effects are expected). , which is obtained by toxicologists based on laboratory tests.

If the exposure dose calculated for the site exceeds the reference dose, that hazard ratio will have a value greater than one and will represent a risk above acceptable. Therefore, measures will have to be taken in this area, such as reducing concentrations or bioavailability.

"If we could reduce the sources of pollution in the country, we would be much better. We have to deal with the solutions, but also with the preventions, about how to avoid clandestine takeovers; everything should be taken care of to avoid polluting sites, "said Rosa María Flores.

Video Medicine: Soil Contamination: Does it Exist Near You? (April 2024).