Gateway test

Updates from the Daily News Blog

Tis the Season for Family and Friends To Think About Going Organic for Safety Reasons—Christmas Trees in Focus
December 19, 2025

Report on Pesticide Contamination of Nation’s Groundwater Shows Widespread Exposure and Health Threats
October 15, 2025

Pesticides Persist in Indoor Dust, Drinking Water and Urine in Households, According to Indiana Study
July 15, 2025

Microplastics Interact with Pesticides, Exacerbating Environmental Health Threats, Studies Find
February 25, 2025

Recent Studies Continue To Highlight Connection Between Depression and Suicide in Pesticide-Exposed Farmers
July 2, 2024

Study Provides First Combined Assessment of Multiple Classes of Pesticides in Human Blood
March 8, 2024

Take Action Today: Tell EPA to Ban Atrazine
March 2, 2020

Pesticides Bound to Particles and Not Detectable in Water Harm Aquatic Organisms
November 23, 2015

Agricultural Insecticides Exceed Regulatory Limits in Surface Water on Global Scale
April 16, 2015

Levels of Pesticides Still a Concern for Aquatic Life in U.S. Rivers and Streams
September 12, 2014

ALL RELATED STORIES >>

Simazine

General Information

• Product Names:

  Princep (Syngenta)
  Algiclear (WECO Products)

• Chemical Class: Chlorinated triazine herbicide
• Uses: Controls most annual grasses and broadleaf weeds before they emerge or after removal of weed growth used for fruit and nut crops, such as apples, oranges, and almonds, in addition to corn, forestry sites and on turfgrass (residential and comerically grown) industrial sites, highway medians and shoulders, railroad rights-of-way, lumberyards, petroleum tank farms; also used as an algaecide in small ornamental ponds and aquariums.
• Alternatives: Organic agriculture, Organic christmas trees, Least-toxic weed control
• Beyond Pesticides rating: Toxic

Health and Environmental Effects

• Cancer: Not documented
• Endocrine Disruption: Yes (1)
• Reproductive Effects: Yes (2)
• Neurotoxicity: Not documented
• Kidney/Liver Damage: Yes (3)
• Sensitizer/ Irritant: Not documented
• Birth/Developmental: Yes (4)
• Detected in Groundwater: Frequently (5)
• Potential Leacher: Yes (4)
• Toxic to Birds: Not documented
• Toxic to Fish/Aquatic Organisms: Yes (4)
• Toxic to Bees: Not documented

Additional Information

• Regulatory Status:
  • EPA Reregistration Eligibility Decision (RED) signed (4/2006)
  • BP Comments December 2025
• Supporting information:
  • Extoxnet Simazine Factsheet (Extension Toxicology Network)
  • PAN Pesticides Database: Simazine (Pesticide Action Network)
• Studies [compiled from the Pesticide-Induced Diseases Database]
  • Impaired development of female mouse offspring maternally exposed to simazine. Park S, Kim S, et al. 2014. Environ Toxicol Pharmacol. 38(3):845-51
  • The influence of polyethylene microplastics on pesticide residue and degradation in the aquatic environment. Wang, F., Gao, J., Zhai, W., Liu, D., Zhou, Z., & Wang, P. (2020). The influence of polyethylene microplastics on pesticide residue and degradation in the aquatic environment. Journal of hazardous materials, 394, 122517. https://doi.org/10.1016/j.jhazmat.2020.122517
  • A regional assessment of chemicals of concern in surface waters of four Midwestern United States national parks. Elliott, S. M., & VanderMeulen, D. D. (2017). A regional assessment of chemicals of concern in surface waters of four Midwestern United States national parks. The Science of the total environment, 579, 1726–1735. https://doi.org/10.1016/j.scitotenv.2016.11.114
  • Occurrence of Current-Use Pesticides in Paired Indoor Dust, Drinking Water, and Urine Samples from the United States: Risk Prioritization and Health Implications. Xie, Y., Li, J., Salamova, A., & Zheng, G. (2025). Occurrence of Current-Use Pesticides in Paired Indoor Dust, Drinking Water, and Urine Samples from the United States: Risk Prioritization and Health Implications. Environmental science & technology, 59(25), 12507–12519. https://doi.org/10.1021/acs.est.5c00961
  • Multidecadal Change in Pesticide Concentrations Relative to Human Health Benchmarks in the Nation’s Groundwater. Stackpoole, S., Lindsey, B. and Nell, C. (2025) National Water Quality Program: Multidecadal Change in Pesticide Concentrations Relative to Human Health Benchmarks in the Nation’s Groundwater, U.S. Geological Survey. Available at: https://pubs.usgs.gov/sir/2025/5081/sir20255081.pdf.
  • Pesticide Prioritization by Potential Biological Effects in Tributaries of the Laurentian Great Lakes. Oliver, S.K., Corsi, S.R., Baldwin, A.K., Nott, M.A., Ankley, G.T., Blackwell, B.R., Villeneuve, D.L., Hladik, M.L., Kolpin, D.W., Loken, L., DeCicco, L.A., Meyer, M.T. and Loftin, K.A. (2023), Pesticide Prioritization by Potential Biological Effects in Tributaries of the Laurentian Great Lakes. Environ Toxicol Chem, 42: 367-384. https://doi.org/10.1002/etc.5522