It is not known whether atrazine or its metabolites can be transferred from a pregnant mother to a developing fetus through the placenta or from a nursing mother to her offspring through breast milk. If your doctor finds that you have been exposed to significant amounts of atrazine, ask whether your children might also be exposed.
Your doctor might need to ask your state health department to investigate. Only certain people can use atrazine because it is a Restricted Use Pesticide RUP , so most people cannot purchase it freely or use it. Since most people cannot purchase it for private use, one way you can reduce your risk of exposure to atrazine is by avoiding areas where it is being used on crops or for control of weeds.
You can also reduce your risk of exposure by avoiding digging or working in soils where it has been applied. If you live in an area where atrazine is used, you may wish to avoid being near the area when it is being applied. If children play in or near areas where it atrazine has been applied too soon after it has been applied, they can be exposed to the herbicide.
You should encourage your children to not play in these areas. Atrazine has been found in water collected from many drinking water wells in the Midwestern United States. Therefore, you may be able to reduce your risk of exposure to atrazine by ensuring that your water supply is free of atrazine, or contains no measurable levels of atrazine.
Atrazine has also been found in streams, rivers, and lakes near fields where it has been applied. Higher amounts have been found in these waterways in the spring and summer months.
Therefore, you may wish not to swim in, nor drink from, these bodies of water. Children may be exposed to atrazine if they play in fields where atrazine has been applied or in streams receiving runoff from those fields.
They should be encouraged not to play in these fields or bodies of water. Low amounts of atrazine have also been found in carpet and house dust in homes in the Midwest. However, very few children living in these homes have had any atrazine in their bodies. To prevent possible exposure of yourself or your children to atrazine, you may wish to vacuum floors and dust surfaces on a frequent basis, especially during the spring and summer months.
If you are a worker who applies atrazine to crops or for weed control, you can reduce your exposure to atrazine by using it according to instructions and wearing proper clothing and protective gear. Be sure to follow all instructions and heed any warning statements. Specific and sensitive tests have been developed to detect atrazine in blood, fat, semen, and breast milk of exposed individuals.
Because atrazine is removed from the body relatively quickly, these tests are only useful in detecting recent exposures within hours and are not useful for detecting past exposures to atrazine. These tests currently cannot be used to estimate how much atrazine you have been exposed to or whether adverse health effects will occur.
These tests are not usually performed in a doctor's office because special equipment is required and samples must be sent to a laboratory for testing. More information on tests that detect atrazine and its metabolites can be found in Chapter 7. The federal government develops regulations and recommendations to protect public health.
Regulations can be enforced by law. Recommendations provide valuable guidelines to protect public health but cannot be enforced by law. Regulations and recommendations can be expressed in not-to-exceed levels in air, water, soil, or food that are usually based on levels that affect animals; then they are adjusted to help protect people. Sometimes these not-to-exceed levels differ among federal organizations because of different exposure times an 8 hour workday or a 24 hour day , the use of different animal studies, or other factors.
Recommendations and regulations are also periodically updated as more information becomes available. For the most current information, check with the federal agency or organization that provides it.
Some regulations and recommendations for atrazine include the following:. Atrazine is currently under review for pesticide re-registration by EPA. Therefore, EPA may be contacted for more information about atrazine.
In addition, atrazine is designated as a Restricted Use Pesticide, which means that only certified pesticide applicators can use atrazine.
For more information, please see Chapter 8. You could be exposed to atrazine while using a product or being too close to an application. You could get atrazine on your skin, eyes, or breathe it in.
Very low levels of atrazine may be found in food and drinking water. Tolerances are legal limits set by the U. See the text box about tolerances. Always follow label instructions and take steps to minimize exposure.
If any exposures occur, be sure to follow the First Aid instructions on the product label carefully. For additional treatment advice, contact the Poison Control Center at If you wish to discuss a pesticide problem , please call NPIC at Atrazine is very low in toxicity if breathed in.
Skin exposure to atrazine may cause mild irritation, redness, or swelling. It is not considered a skin sensitizer. This means that allergic reactions after multiple exposures are not likely. If atrazine is eaten, it is low in toxicity. This can tell us how toxic a chemical is. Something that is highly toxic may kill a person with a very small amount of chemical. If something is very low in toxicity, it may take much more for that same person to become very sick or die.
When rats ate enough atrazine to almost kill them, they had increased activity followed by slowing, incoordination, and muscle spasms. Atrazine does not easily pass through the skin.
In a study with monkeys, atrazine was highest in blood plasma within 1 hour. The plasma half-life was 4 hours. Metabolites of atrazine had half-lives of 2. It is excreted in the urine and feces. Urinary excretion of atrazine peaked days after exposure. Atrazine does not alter or damage genes in humans and animals. However, these tumors were not considered relevant to humans by a scientific advisory panel. This was because of differences in rat and human female reproductive systems.
They also lost weight and had difficulty moving. They also had enlarged hearts with fluid inside the heart's membrane. This started when they were 8 weeks old.
After 3 months, half the rats in each group were then fed a high-fat diet instead of regular rat chow.
Rats who drank the treated water used less energy when they were sitting still. They also gained weight and became insulin resistant. This happened even though their food intake and activity level did not change. The high-fat diet made the weight gain and insulin resistance worse. They lost more pregnancies than rabbits who did not get atrazine.
The rabbit litters had fewer and smaller babies. They also showed slower bone formation. However, the mothers and pups weighed less. Its movement downward through the soil, or leaching, is limited by its ability to attach itself to soil particles. Soils high in clay and organic matter content are less likely to let atrazine move downward than sandy soils.
Atrazine will generally stay in the upper 1 to 6 inches of the soil profile on most agricultural soils. The presence of atrazine in surface water runoff is of greatest concern. Atrazine can be washed off the site of application to other sites where non-tolerant vegetation grows. It also can be carried into streams and other tributaries that flow into surface water that may be used as a source for drinking water.
Atrazine has been detected at very low levels in surface waters at several locations throughout Texas. However, such occurrences are few considering its widespread use. Normal water purification systems used by municipalities do not remove atrazine from the water. To answer this question, consider the following points. Toxicity is usually defined in two ways—acute or chronic. Acute toxicity refers to the amount that would be required to cause a specific effect when taken at one time, while chronic toxicity refers to the amount that can cause an effect if taken continuously over a long period of time.
The table below compares the acute toxicity from most to least of some common materials to atrazine note that a higher LD50 is less toxic. We demonstrated that encapsulation not only maintained the mechanism of action of atrazine, but also potentiated its post-emergence herbicidal activity against this target species, as compared to the effects of a commercially available atrazine product.
As a result, a fold reduction of the atrazine dosage was achieved, without compromising the biological activity of the herbicide. A greater pre-emergence herbicidal activity of atrazine-containing PCL nanocapsules against mustard seedlings has also been shown Pereira et al.
Therefore, we decided to investigate whether these nanoformulations might have any deleterious effects on non-target crops. This is an essential test before such systems can be recommended for safe use in agriculture. In the present study, we evaluated the effects of pre- and post-emergence treatments with PCL nanocapsules containing atrazine on growth, physiological and oxidative stress parameters of maize Zea mays L.
The effects of PCL nanocapsules without the herbicides were also determined. Overall, we observed that PCL nanocapsules containing or not atrazine did not lead to persistent deleterious effects in maize plants, indicating that the technique could offer a safe tool for weed control without affecting crop growth. This technique, based on interfacial polymer deposition, consists of mixing an organic phase into an aqueous phase. The aqueous phase was composed of 30 mL of a solution containing 60 mg of polysorbate 80 surfactant Tween The organic phase was slowly inserted into the aqueous phase, under magnetic stirring at room temperature, and maintained under agitation for 10 min.
Herbicide-free nanoparticles were prepared according to the same procedure, but omitting the atrazine. All other reagents analytical grade used to prepare the PCL nanocapsules were purchased from local suppliers. Zea mays L. The soil was the same Rhodic Ferralsol as used in our previous study Oliveira et al. The substrate was supplemented with 50 mL of complete Hoagland and Arnon's nutrient solution, on a weekly basis.
Throughout the cultivation 14 days until treatments , the plants were kept in a greenhouse under natural conditions of light and temperature. The experiments were carried out from October to March spring-summer.
The average daily values of temperature, relative humidity, and accumulated global solar radiation were For post-emergence assays, four individuals were retained per pot after germination.
Each pot was sprayed with 3. The treatments were applied between and am. Macroscopic symptoms in the leaves were recorded using a Samsung STF camera. The physiological and oxidative stress parameters were determined 1, 2, 4, and 8 days after treatment. The dry weight analysis was measured at harvest. For pre-emergence assays, six seeds were sown per pot.
The pots were then sprayed with the same formulations described for the post-emergence assays. The physiological, oxidative stress, and dry weight analyses were carried out 3 weeks after emergence of the plants. Lipid peroxidation was analyzed as a marker of oxidative stress. Freshly collected leaves mg were homogenized with cold TCA 0. Sixteen biological replicates were used for weight analysis, nine for gas exchange experiments, and five for chlorophyll fluorescence and oxidative stress analyses.
These results are coherent with the inhibitory action of atrazine in PSII. Figure 1. Maximum photosystem II quantum yields of maize plants submitted to post-emergence treatment with the formulations. Chlorophyll fluorescence parameters were evaluated 1, 2, 4, and 8 days after the plants were sprayed with 3.
Stomatal conductance, intercellular CO 2 concentration, and transpiration were not affected by any of the formulations tested data not shown. Figure 2. Net photosynthesis of maize plants submitted to post-emergence treatment with the formulations.
Net photosynthesis was evaluated 1, 2, 4, and 8 days after the plants were sprayed with 3. Figure 3. Leaf lipid peroxidation of maize plants submitted to post-emergence treatment with the formulations.
Lipid peroxidation was evaluated 1, 2, 4, and 8 days after the plants were sprayed with 3. No macroscopic symptoms were observed in leaves sprayed with any of the formulations Figure 4. Accordingly, none of the tested formulations affected the shoot dry weight of the maize plants Figure 5. Figure 4. Symptom evolution in maize leaves submitted to post-emergence treatment with the formulations. Symptoms were recorded 8 days after the plants were sprayed with 3. Figure 5. Shoot dry weight of maize plants submitted to post-emergence treatment with the formulations.
Shoots were sampled 8 days after the plants were sprayed with 3. Figure 6. Effect on maize plants of pre-emergence treatment with the formulations. Maize seeds were germinated in a soil:vermiculite mixture sprayed with 3. Shoot dry weight A , maximum quantum yield of photosystem II B , net photosynthesis C , and leaf lipid peroxidation D were evaluated 3 weeks after emergence of the plants. PCL nanocapsules have emerged as an efficient carrier system for atrazine Grillo et al.
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