Adverse Effects:

Anemia
Blood
Body Weight Decrease
Bone
Endocrine: Testicular
Endocrine: Thyroid
Kidney
Liver
Spleen

Environmental Effects:

Toxic to plants and algae

The following data is primarily for Primisulfuron-methyl

Regulatory Information (only comprehensive for the US)
Note: PAN presents its data as one for both herbicides

Beacon
CGA 136872
Rifle
Tell  

March 24, 1994. Primisulfuron-methyl. New York State approval of label addition of the use of Beacon Herbicide for aerial use. Letter from Normal Nosenchuck, director, NYS Div. of Hazardous Substances Regulation to Ciba Plant Protection.

"... The active ingredient methyl primisulfuron is registered for weed control on field corn and popcorn in New York State. The submitted Special Local Need (SLN) label expands usage to allow aerial application ... Both the New York State-Department of Health and this Department's Division of Fish and Wildlife have agreed that the 150 foot buffer zone incorporated in the SLN label will minimize any adverse impact caused by aerial spraying of this pesticide product. This conclusion was reached after evaluation cf drift studies submitted by Ciba Plant Protection demonstrated that, under the conditions of these submitted studies, spray drift may occur. Also, the Division of Fish and Wildlife has determined from experience with mosquito control programs that aerial applications can be made with accuracy within this established buffer zone."

Rationale for US EPA to add Primisulfuron methyl to the Toxic Release Inventory

In a 90-day dog feeding study, reduced thyroid weights accompanied by colloid depletion and parafollicular hyperplasia and anemia were observed at the LOEL of 25 mg/kg/day. The NOEL was 0.625 mg/kg/day. In a 1-year dog study, dietary administration of 250/125 mg/kg/day (LOEL: the dose was changed after week 10 in the study) produced thyroid hyperplasia, anemia, increased platelet levels, vacuolar changes, and increased absolute and relative liver weights. The NOEL was 25 mg/kg/day. In an 18-month study in mice, dietary administration of 1.7 mg/kg/day produced increased absolute and relative liver weights in females. No NOEL was established. Based on this study, an oral RfD of 0.006 mg/kg/day was derived. In a 2-year mouse study, increases in absolute and relative liver weights were observed at 408 mg/kg/day in males and 1.7 mg/kg/day in females. The systemic LOEL and NOEL in males was 408 mg/kg/day and 40.2 mg/kg/day, respectively. The systemic LOEL in females was 1.7 mg/kg/day and a NOEL could not be established. EPA believes that there is sufficient evidence for listing primisulfuron on EPCRA section 313 pursuant to EPCRA section 313(d)(2)(B) based on the available thyroid and liver toxicity data for this chemical.

Plant toxicity values include a duckweed 14-day EC 50 of 0.27 ppb and an algae 7-day EC 50 of 24 ppb. EPA believes that there is sufficient evidence for listing primisulfuron on EPCRA section 313 pursuant to EPCRA section 313(d)(2)(C) based on the available environmental toxicity data for this chemical.

Ref: USEPA/OPP. Support Document for the Addition of Chemicals from Federal Insecticide, Fungicide, Rodenticide Act (FIFRA) Active Ingredients to EPCRA Section 313. U. S. Environmental Protection Agency, Washington, DC (1993).
As cited by US EPA in: Federal Register: January 12, 1994. Part IV. 40 CFR Part 372. Addition of Certain Chemicals; Toxic Chemical Release Reporting; Community Right-to-Know; Proposed Rule.

Note:
Addition of Certain Chemicals; Toxic Chemical Release Reporting; Community Right-to-Know. Final Rule.
Primisulfuron was included in the deferral of 40 chemicals: EPA is deferring final action on 40 chemicals and one chemical category until a later date. These chemicals and the comments received on them raised particularly difficult technical or policy issues which will require additional time to address. The Agency does not believe that it would be in the spirit of community right-to-know to delay final action on the remaining 286 chemicals and chemical categories, pending completion of work on the more limited group. In a future rulemaking, EPA will make a final determination as to whether these chemicals should be added to EPCRA section 313. The public comment that has been received specific to these deferred chemicals will be addressed as part of the future rulemaking discussed above.

Primisulfuron-methyl. Report of the FQPA Tolerance Reassessment Progress and Risk Management Decision (TRED); Notice of Availability. EPA has reassessed the 24 tolerances, or legal limits, established for residues of primisulfuron-methyl in/on raw agricultural commodities in the TRED report (a shortened TRED Fact Sheet is also available). These tolerances are now considered safe under the Federal Food, Drug, and Cosmetic Act (FFDCA), as amended by the FQPA of 1996. Therefore, 23 existing tolerances for primisulfuron-methyl have been reassessed and remain unchanged, and 1 tolerance on sweet corn will be revoked because current labels prohibit use on sweet corn. Although EPA is considering a petition for a new use on Kentucky bluegrass grown for seed, the Agency has not yet made a decision to register this new use or establish any associated tolerances. EPA is issuing the primisulfuron-methyl TRED as a final decision without a formal public comment period.

Addition of Certain Chemicals; Toxic Chemical Release Reporting; Community Right-to-Know. Final Rule.

EPA is deferring final action on 40 chemicals and one chemical category until a later date. These chemicals and the comments received on them raised particularly difficult technical or policy issues which will require additional time to address. The Agency does not believe that it would be in the spirit of community right-to-know to delay final action on the remaining 286 chemicals and chemical categories,
pending completion of work on the more limited group. In a future rulemaking, EPA will make a final determination as to whether these chemicals should be added to EPCRA section 313. The public comment that has been received specific to these deferred chemicals will be addressed as part of the future rulemaking discussed above. These chemicals follow:
primsulfuron