Post by account_disabled on Mar 11, 2024 3:20:02 GMT -5
A research team showed, in a document, that it found the pesticide DDT in Canadian lakes half a century after it was banned. This affected key aquatic species and potentially food networks throughout the ecosystem.
According to the study's lead author, Dr. Josh Kurek, assistant professor of Geography and Environment at Mount Allison University, “what was considered yesterday's environmental crisis in the 1950s to 1970s is still today's problem.” ”.
“Decades of intense insecticide applications France Mobile Number List in our coniferous forests have left a lasting mark on these lakes, and likely many others in eastern North America.”
Between 1952 and 1968, more than 6,280 tons of dichlorodiphenyltrichloroethane or DDT were sprayed from airplanes over forests on the Atlantic coast of Canada, in the province of New Brunswick, to control pest outbreaks in forests exploited by the forestry industry. according to the Canadian Ministry of the Environment. The maneuver is considered one of the largest aerial spraying programs in North America.
The pesticide DDT was recently found in Canadian lakes half a century after it was banned.
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Public knowledge of the harmful effects of DDT on wildlife and the environment led to the regulation of its use until it was completely banned in 1972.
Lake sediments provide a powerful and well-recognized archive of environmental conditions, allowing researchers to evaluate chemical and biological conditions in lakes before, during, and after pesticide use.
DDT levels in the lake sediments were among the highest found in previously sprayed areas of Canada and the United States, or suggestive of very heavy past pesticide use.
Surprisingly, DDT and its toxic breakdown products are still very high in modern sediments, above levels where harmful biological effects tend to occur.
However, a group of researchers from Mount Allison University in New Brunswick recently found traces of DDT in lake sediments that “still exceed levels considered safe for aquatic organisms,” they said in a statement.
In addition, a potential risk was found with DDT, since it can spread through the local food web, beyond the shores of the lakes.
These findings were published in the journal of environmental science and technology of the American Chemical Society (ACS).
Data from Newsweek says that the team of researchers collected samples from five lakes in New Brunswick and analyzed not only the concentration of DDT but also partially fossilized remains of water fleas (Cladocera). They found that in most lakes there was a change in the existing animal plankton species, from larger ones to smaller ones, which are generally more resistant to contaminants.
Scientists speculate that aquatic organisms that have been exposed to significant amounts of sedimentary DDT “may have high levels of DDT in their tissues.”
An invertebrate with DDT can be the food of a trout, which in turn is eaten by local fauna or ends up in a fisherman's net, thus transferring the toxic insecticide “from the aquatic to the terrestrial ecosystem,” the research indicates.
According to the study's lead author, Dr. Josh Kurek, assistant professor of Geography and Environment at Mount Allison University, “what was considered yesterday's environmental crisis in the 1950s to 1970s is still today's problem.” ”.
“Decades of intense insecticide applications France Mobile Number List in our coniferous forests have left a lasting mark on these lakes, and likely many others in eastern North America.”
Between 1952 and 1968, more than 6,280 tons of dichlorodiphenyltrichloroethane or DDT were sprayed from airplanes over forests on the Atlantic coast of Canada, in the province of New Brunswick, to control pest outbreaks in forests exploited by the forestry industry. according to the Canadian Ministry of the Environment. The maneuver is considered one of the largest aerial spraying programs in North America.
The pesticide DDT was recently found in Canadian lakes half a century after it was banned.
Tweet this phrase.
Public knowledge of the harmful effects of DDT on wildlife and the environment led to the regulation of its use until it was completely banned in 1972.
Lake sediments provide a powerful and well-recognized archive of environmental conditions, allowing researchers to evaluate chemical and biological conditions in lakes before, during, and after pesticide use.
DDT levels in the lake sediments were among the highest found in previously sprayed areas of Canada and the United States, or suggestive of very heavy past pesticide use.
Surprisingly, DDT and its toxic breakdown products are still very high in modern sediments, above levels where harmful biological effects tend to occur.
However, a group of researchers from Mount Allison University in New Brunswick recently found traces of DDT in lake sediments that “still exceed levels considered safe for aquatic organisms,” they said in a statement.
In addition, a potential risk was found with DDT, since it can spread through the local food web, beyond the shores of the lakes.
These findings were published in the journal of environmental science and technology of the American Chemical Society (ACS).
Data from Newsweek says that the team of researchers collected samples from five lakes in New Brunswick and analyzed not only the concentration of DDT but also partially fossilized remains of water fleas (Cladocera). They found that in most lakes there was a change in the existing animal plankton species, from larger ones to smaller ones, which are generally more resistant to contaminants.
Scientists speculate that aquatic organisms that have been exposed to significant amounts of sedimentary DDT “may have high levels of DDT in their tissues.”
An invertebrate with DDT can be the food of a trout, which in turn is eaten by local fauna or ends up in a fisherman's net, thus transferring the toxic insecticide “from the aquatic to the terrestrial ecosystem,” the research indicates.