In samples analyzed by Universidad Nacional de Colombia (UNal) in Palmira and Universidad de Pamplona (Province of Norte de Santander) researchers, the grass was tainted on the leaves, stalks and roots due to waste released by the oil industry and absorbed by the soil and therefore to crops and grasses.
Furthermore, thanks to the contributions from other research projects they also discovered presence and damaging effects in animals. Researchers discovered lead, cadmium, molybdenum and zinc in 40 slaughtered cattle from the Barrancabermeja slaughterhouse which had been brought from cattle farms near oil industries.
UNal Professor and PhD in Agricultural Sciences Manuel José Peláez said that Brachiaria pastures are tolerant or have coadapted to said metal metalliferous environments and are tainted mainly in the first 5 cms (1.9 in.) of the roots.
In the study areas (Provinces of Antioquia and Santander, and particularly the city of Barrancabermeja, home to the largest oil refinery in Colombia) they discovered 192 plant species mostly belonging to the Poaceae and Fabaceae families, representing 44.2% and 24.4% respectively of the totally plant families explored. The Poaceae family includes Brachiaria spp. which B. decumbens and B. humidicola are among the 10 most tainted species.
To analyze the material they took grass samples which were taken to the UNal-Palmira Laboratory of Botany to identify family, genus and species. Other samples were sent to the Laboratory of Analytical Chemistry of the Universidad de Pamplona, to analyze the concentration of metal in the soil. They also observed damages through microscopy techniques in root, stalk and leaf tissue.
They discovered that heavy metal load in grass represents damage to animals and therefore to the rest of the food chain.
To inquire presence of heavy metals in grass and its effects in animals Professor Peláez worked with John Jairo Bustamante Cano, a Universidad de León (Spain) Veterinarian and PhD in Medicine and Animal Surgery.
The amounts discovered in cattle were within permissible levels according to Codex Alimentarius and European Union (EU) standards, which state they should be below 0.05. However cattle coming from the municipality of Yondó surpassed the aforementioned levels.
“According to the previous, when analyzing lead levels from Barrancabermeja, they proved that 90% of the liver, 75% kidney, 85% muscle and 5% skin samples exceeded the upper limits of the standards mentioned above. A similar scenario happened with cadmium as 85% of the liver, and 10% of the kidney and muscles samples surpassed the accepted EU levels,” said Bustamante.
According to Bustamante, living organisms which eat heavy metal tainted foods will suffer from kidney issues, specifically in the tubules which direct urine to the bladder; as well as in the blood as they impact the red blood cell counts, producing anemia.
Regarding human health Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez’ (National Neurology and Neurosurgery of México) Experimental Pathology Laboratory researchers Concepción Nava Ruiz and Marisela Méndez Armenta, say in a scientific article (The Neurotoxic Effect of Heavy Metals (cadmium, lead, arsenic and thallium) that cadmium impacts organs and tissues such as the kidneys as it produces chronic kidney disease. It also produces aortic and coronary arteriosclerosis in the heart. Furthermore bones, testicles, placenta, and the central and peripheral nervous system area also impacted.
The Colombian Petroleum Company (Ecopetrol, for its Spanish acronym) claims having technologically evaluated production fields based on an environmental management plan with invertebrate aquatic organisms (Daphnia pulex), fish (Oreochromis sp.) and algae (Selenastrum capricornutum). “We have not carried out toxicology research due to our oil activity in plants and human beings,” said Alba Liliana Barragán Ortiz, Ecopetrol Management Assistant.
Agencia de Noticias UNAL |