Promecarb

(endorsed 2011)

Guideline

The health concerns associated with promecarb have not been fully evaluated and therefore a health-based guideline value for promecarb in drinking water cannot be set.

Related chemicals

Promecarb (CAS 2631-37-0) belongs to the carbamate class of chemicals. There are many other pesticides in this class, which includes aldicarb, carbaryl and methomyl (Tomlin 2006).

Human risk statement

There are currently insufficient data on which to base a human risk statement.

With good water quality management practices, pesticides should not be detected in source waters used for drinking water supplies. Persistent detection of pesticides may indicate inappropriate use or accidental spillage, and investigation is required in line with established procedures in the risk management plan for the particular water source.

General description

Uses: Promecarb is an insecticide formerly used to control lepidopterous pests, leaf miners of fruits, Colorado potato beetle and common rootworm, in agriculture and the home garden.

There are no registered products containing promecarb in Australia, but de-registered compounds may still be detected in water. Previously registered products were intended for both professional and home garden use.

Exposure sources: If used in the future, the main source of public exposure to promecarb and its metabolites would be residues in food. Residue levels in food produced according to good agricultural practice are generally low.

Agricultural use of promecarb in the future may potentially lead to contamination of source waters through processes such as run-off, spray drift or entry into groundwater.

Typical values in Australian drinking water

No occurrence data on promecarb in Australian waters could be found.

Treatment of drinking water

No information on efficiency of drinking water treatment to remove promecarb could be found.

Measurement

Promecarb can be measured by routine gas chromatography–mass spectrometry analysis, with a limit of reporting of 1 µg/L (Queensland Health, 2007).

History of the health values

There is currently no acceptable daily intake (ADI) or acute reference dose (ARfD) value for promecarb.

The previous health value was 0.03 mg/L.

Health considerations

Metabolism: Promecarb is well absorbed from the gastrointestinal tract, extensively metabolised and rapidly excreted, mainly via the urine.

Acute effects: Promecarb has high acute oral toxicity and moderate acute dermal toxicity. It is unknown whether promecarb is a skin sensitiser. In rats, inhibition of plasma, brain and red blood cell cholinesterase was observed after a single oral dose of 10 mg/kg bw. Recovery was seen within 24 hours.

Short-term effects: In 3-month oral studies in mice, there was increased mortality, decreased bodyweight gain, severe hyperglycemia, decreased spleen and ovarian weights, and liver degeneration at 8.9 mg/kg bw/day and above.

In 3-month dietary studies in rats and dogs, no treatment-related effects were observed up to 20 mg/kg bw/day in rats and up to 5 mg/kg bw/day in dogs. These were the highest doses tested for each species.

Long-term effects: In an 18-month dietary study in rats, there were no clinical signs of toxicity at 20 mg/kg bw/day, the highest dose tested (cholinesterase activity was not measured).

Carcinogenicity: In an 18-month study in rats, there was no evidence of carcinogenicity for promecarb.

Genotoxicity: Only short-term in vitro studies are available; these report no evidence that promecarb is genotoxic.

Reproductive and developmental effects: There were no reproduction studies available. In a developmental study in rats, maternotoxicity and delayed ossification in the foetus occurred at 5 mg/kg bw/day.

Poisons Schedule: Promecarb was removed from Schedule 6 of the Standard for the Uniform Scheduling of Drugs and Poisons in August 1993 due to concerns over the lack of toxicity and residue data. Current versions of the Standard for the Uniform Scheduling of Medicines and Poisons (the Poisons Standard)(DoHA 2010) should be consulted for further information.

Derivation of the health-based guideline

There are currently insufficient data on which to establish a health-based guideline for promecarb in drinking water in Australia.

References

NOTE: The toxicological information used in developing this fact sheet is from reports and data held by the Department of Health, Office of Chemical Safety.

DoHA (2010) The Poisons Standard; Schedule 1-Standard for the Uniform Scheduling of Medicines and Poisons, Department of Health and Ageing, Commonwealth of Australia, Canberra.

Queensland Health (2007). Organochlorine, organophosphorous and synthetic pyrethroid pesticide, urea and triazine herbicides and PCBs in water. QHFSS SOP 16315.

Tomlin CD (ed) (2006). The Pesticide Manual: a world compendium, 14th edition, British Crop Production Council, UK.