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Mozambique - Final Regulatory Action
Terbufos CAS number:
Date circular:

Chemical name: Phosphorodithioic acid, S-[[(1,1-dimethylethyl)thio]methyl] O,O-diethyl ester

Final regulatory action has been taken for the category: Pesticide

Final regulatory action: The chemical is Banned

Use or uses prohibited by the final regulatory action:

Ban all formulations and for all uses.

Pesticide use or uses that remain allowed:


The final regulatory action was based on a risk or hazard evaluation: Yes

Summary of the final regulatory action:

Based on the decision Nr 001/DNSA/2014 terbufos was banned by the National Directorate of Agrarian Services from further import and use in Mozambique. The ban of all uses and the cancellation of the products containing terbufos in the country was decided due to the toxic nature and hazardous properties of this active substance which combined with the improper use in the country due to the local specific conditions of use can damage human and animal health. The decision to cancel the registration of terbufos was taken as the last step of the project for Risk Reduction of Highly Hazardous Pesticides, which identified Highly Hazardous Pesticides that are registered in Mozambique. After consultations with different actors (public sector, private sector, civil society and others), cancelation of registrations and consequent non-approval for their use in Mozambique was approved.

The reasons for the final regulatory action were relevant to: Human health

Summary of known hazards and risks to human health:

A project entitled Reducing Risks of Highly Hazardous Pesticides (HHPs) in Mozambique was initiated by the Government of Mozambique with the objective to reduce the greatest risks associated with pesticide use in the country. The ultimate goal was to develop and implement an HHP Risk Reduction Action Plan for the most dangerous pesticides and use situations, resulting over time in the implementation of a variety of risk reduction measures based on a review of use conditions.
In the first step of the project, a review of all the pesticides registered in Mozambique was carried out and a shortlist of highly hazardous pesticides was established. This shortlist was based on an assessment of the hazards of the pesticides, based on criteria established by the FAO/WHO Joint Meeting on Pesticide Management (JMPM) (FAO/WHO, 2008).
During the second step of the project, a use survey was carried out in selected regions and cropping systems in Mozambique. The main goal of the survey was to identify the conditions under which pesticides are being used in the country and their contribution to potential risks for human health and the environment.
The third step of the project consisted of a stakeholder consultation to further discuss the use and risks of highly hazardous pesticides in Mozambique and fine-tune the shortlist based on the survey results and the expertise and experience of stakeholders.
As result, a short list of HHPs, including coming close to HHPs, which were used in the country, was established.
Terbufos was shortlisted as HHP based on the following FAO/WHO Joint Meeting on Pesticide Management (JMPM) criterion for identification of HHPs:
-pesticide formulations that meet the criteria of classes Ia or Ib of the WHO Recommended Classification of Pesticides by Hazard;
To evaluate this criterion, all pesticide formulations registered in Mozambique were classified using the above mentioned hazard classification. The oral and dermal LD50 value of the formulation, as provided in the registration dossier, was used as the basis for the classification.
LD50 values for the formulation were available or could be estimated for all registered pesticide products except for three microbial pesticides and one citronella oil (i.e. > 99% of the total).
Terbufos formulations were identified as Extremely hazardous Class Ia according to the JMPM criteria for HHPs based on the WHO International Classification of pesticides by hazards, and therefore considered and shortlisted as HHP (Come A.M.& van der Valk H., 2014.)
Terbufos a.i. was not registered in EU, whereas was registered in the US at the time of the study.
Additionally conducted desk study to assess the environmental hazards associated with pesticides imported in Mozambique from 2002 to 2011 Alterra, Wageningen UR, also identified Terbufos as a pesticide of primary concern for the country considering its acute toxicity hazardous properties according to WHO classification of hazards (Lahr J., R. Kruijne & J. Groenwold, 2014).
During the second phase of the project field surveys on the pesticide use and exposure were carried out.
The surveys (325 subsistence farmers interviewed) revealed that most of the farmers applied pesticides (95%), and that the conditions of use were likely to result in undue (excessive) exposure. Half of the farmers interviewed never received any training on pesticides use, and even the other half that did, often lacked understanding of the risks involved. Farmers were spraying vegetable crops at least 14 times per growing season. One out of three applications was involving one of the HHP containing formulation (Farmers using HHPs includes almost 30% of the interviewed farmers).
Also almost none of the farmers (93%) owned or wore adequate PPE having only one or no protective items at all. Only 2% of those applying HHPs wore adequate full body protection PPE. About half of the farmers had not received any training on the use of pesticides. The majority of pesticide applicators used manual sprayer (36%), followed by electric sprayer (with batteries); 33% and followed by inappropriate equipment such as watering can (13.5%) or other (unknown) means (12.5%). Approximately about half of the farmers surveyed reported that they noticed to receive pesticide on their clothes, bare skin or eyes when using pesticides. The main health symptoms associated with pesticide use by farmers noticing symptoms were headaches, skin rashes, burning eyes, vomiting, burning nose, blurred vision, dizziness and excessive sweating. Almost half of the farmers declared they did not read pesticide labels, including use instructions such as proper dosage and protective measures, the main reason being illiteracy. One out of four farmers poorly understood the hazard colour band on pesticide labels that indicates acute toxicity.
The survey results showed that the use of pesticides in general, and of HHPs in particular, was likely to result in excessive exposure of farmers in Mozambique. Therefore enforcing risk mitigation measures depending solely on wearing the appropriate PPE under the local conditions of use to be difficult and unlikely to give results.
Terbufos and the products containing this a.i. was considered harmful for the human health under the local conditions of use in Mozambique requiring risk mitigation measures. Therefore the authorities decided to ban the a.i. terbufos from future use in the country and to cancel the registration of all the products containing it.

Expected effect of the final regulatory action in relation to human health:

Reducing the risk posed by the use of HHPs in Mozambique specially terbufos in the context of human health.

Summary of known hazards and risks to the environment:


Date of entry into force of the final regulatory action: 15/07/2014