Environmental impacts of pesticides unearthed
The South African forestry sector’s use of pesticides poses only a low risk to human and environmental health, according to a Nelson Mandela University doctoral study.
PhD graduate Noxolo Ndlovu has shown that foresters continue to protect communities, the soil and aquatic organisms found within and adjacent to forestry plantations through their pesticide usage.
A junior research scientist at KwaZulu-Natal’s NCT Forestry, Ndlovu graduated this month from Mandela University’s George campus with a doctorate in nature conservation — an achievement given the campus’s niche in terms of sustainability studies and practice.
Her thesis, Towards understanding the soil and water fate of pesticides (active ingredients) used operationally in South
African forest plantations, sought to study the impact of forestry pesticides.
“With pesticides being chemical compounds that have a likelihood of causing harm to the environment, it was important to understand whether their use could be causing detrimental impacts,” Ndlovu said.
The good news was that the risk is low, due to a combination of factors.
Pesticides are used in line with product label recommendations and they are not the main method of pest and disease management.
They are applied at low rates and frequencies.
The study was a positive development for growers, SA Forestry Online reported, since they are restricted in terms of the number of pesticides approved for use, and under increasing pressure from environmentalists, consumers and certification bodies to decrease usage of chemical pesticides.
Conducted over a 26-month period at NCT’s Ingwe plantation in the KwaZulu-Natal’s midlands, it covered an area typical of a South African forestry, situated on a steep site with a stream nearby, which therefore represented a worstcase scenario in terms of pesticide residue and run-off, the report said.
Data obtained from Ndlovu’s study was significant, because there was scant research on the environmental impacts of pesticide use in SA forestry conditions.
Another positive development was that the research team used the findings to create a “generic decision support tool” to help guide pesticide use specifically in a South African context.
Born in KwaZulu-Natal’s Tugela Ferry in 1993 to single mother Weziwe Mthembu, Ndlovu was an only child with a passion for nature and education.
“My love for life sciences and natural sciences was inspired by my high school biology teacher, Mrs Gevers, at Greytown High School,” Ndlovu said.