Chemical name: Methane, bromo-

Final regulatory action has been taken for the category: Pesticide

Final regulatory action: The chemical is Severely Restricted

Use or uses prohibited by the final regulatory action:

This regulation applies to all formulations with active ingredient methyl bromide, where there was a severe restriction of these formulations, prohibiting the disinfection of soils and fumigation of stored grains. Additionally, specific measures are established for a controlled use of the substance.

Pesticide use or uses that remain allowed:

The use of gaseous formulations of methyl bromide is allowed for quarantine treatment in the control of quarantine pests in agricultural products and packaging at ports and border crossings, until a viable substitute is found that allows their replacement. Requiring the use of airtight fumigation chambers.

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

Summary of the final regulatory action: Resolution 2152 of 1996 of the Ministry of Health established that Methyl Bromide is an extremely toxic pesticide for humans and that this substance has in turn been identified as one of the most powerful atmospheric ozone depletors. In addition, there are viable substitutes for Methyl Bromide in fumigation of stored grains and for soil disinfection.

Subsequently, modifications were made to article 1 of resolution 2152 in order to make a more controlled and restrictive use of the substance, such modifications were made through resolutions 00643 of 2004, 01800 of 2006, 03587 of 2008 and the resolution 5049 of 2008. Currently, resolution 2152 of 1996 and resolution 5049 of 2008 are in force.

The latter defines all the restrictions in force for the use of methyl bromide, establishing: "ART. 1º - Modify Article 1 of Resolution 2152 of 1996, as amended by resolutions 643 of 2004 and 1800 of 2006, which will read as follows:

Considering the above, this notification refers to final regulatory action 5049 of 2008.

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

Summary of known hazards and risks to human health:

In Resolution 2152 of 1996 it is stated that 'pesticide METHYL BROMIDE is an irritating and vesicant gas, extremely toxic to humans that affects different organs and systems, with a high potential risk of producing acute poisoning by inhalation and absorption through the skin and mucous membranes'. This was established from the toxicological concept issued by the Ministry of health in May 1992 (Annex II).

This concept was developed considering the provisions on the use and management of pesticides, established in Decree 1843 of 1991 and the criteria established in Resolution 10834 of 1992 (Annex XIV), such as: the Oral Median Lethal Dose and dermal and inhalation mean lethal concentration in rats, chronic toxicity studies, potential carcinogenic, mutagenic and teratogenic effects; presentation and formulation; form and dose of application; persistence and degradability; acute, sub acute and chronic toxic effects in humans and animals; feasibility of medical diagnosis and treatment with full recovery, short-term environmental effects. With regard to the lethal doses and the average lethal concentration, Colombia took into account the tables presented below:

Table 1. Toxicological categories according to LD50

CATEGORY LD50, rats (mg/kg body weight) Oral Dermic *Solids *Liquids *Solids *Liquids I. EXTREMELY TOXIC 5 or less 20 or less 10 or less 40 or less II. HIGHLY TOXIC 5 up to 50 20 up to 200 10 up to 100 40 up to 400 II. MEDIUM TOXIC 50 up to 500 200 up to 2000 100 up to 1000 400 up to 4000 IV. SLIGHTLY TOXIC 500 2000 1000 4000 *The terms solid and liquid refer to the physical state of the active ingredient of the formulations object of the classification.

Table 2. Toxicological categories according to LD50

CATEGORYLD50, mg/1 Air, 4h I. EXTREMELY TOXICup to 0.5 II. HIGHLY TOXIC0.5 up to 2 II. MEDIUM TOXIC2 up to 20 IV. SLIGHTLY TOXIC 20 Additionally, methyl bromide was identified "as one of the most powerful depletors of atmospheric ozone and therefore indirectly favours the effects of solar radiation in the production of skin cancer (Scientific, Technical and Economic Review of the Committee of Experts of the Montreal Protocol on METHYL BROMIDE) ". This implies that, by reducing the use of methyl bromide in Colombia, we are contributing to the reduction of emissions of an ozone layer depletory and, indirectly, to reducing the risk of skin cancer by increased solar radiation.

This was also supported by the 1989 report of the Montreal Protocol, which defines that "skin cancer will increase with any increase in UV-B radiation, the relationship between skin cancer and ozone decrease is not one to one: For every 1% decrease of the total ozone will result in a 3% increase in the incidence of melanoma or skin cancer" and this was considered in the development of regulation 2151, 1996 (Annex XV page II).

In addition to the problems at skin level due to the exposure increase to UV-B radiation caused by the loss of stratospheric ozone, it has also been identified that the incidence of cataracts and the severity of different infections has been increased since the immune system is supressed from radiation. Annex IV Report of the Panel on Environmental Effects p. 11-24

It is important to highlight that in the UNEP Methyl Bromide reports in 1992 and 1994, one of the sources of exposure to this evaluated pesticide was the use in pre-sowing and post-harvest agricultural activities, fumigations in structures (such as containers and buildings) and in intermediate chemicals. Additionally, a predictive theoretical analysis identified that between 45 and 53% of the amount used in agricultural activities could be released into the atmosphere (Annex V p. 10-7). This was expected to happen in Colombia since Methyl Bromide was used as a soil fumigant, for stored grains, and as quarantine fumigant. Specifically, in soils treatment it was used to eliminate weeds, nematodes and fungi, that frequently made necessary to disinfect the substrate used, the amounts of use as a soil fumigant are presented in table 3 (this information is available to the general public in Annex VI).

Table 3. Main users of Methyl Bromide as soil fumigant, Colombia 1994

SECTORESTIMATED REPORTED AMOUNT OF METHYL BROMIDE USED kgESTIMATED PRODUCTION AREA (1994) HaBANANA3200045000STRAWBERRY50100CHRYSANTHEMUMNot specified350FOLIAGE PLANTS Reported use200TOBACCO (SEED)Reported use 3000FOREST-TREES (NURSERIES)Reported use15000MELÓNReported use250COFFEE (SEED)Reported use100000Source: UNDP Regional survey on Methyl Bromide- Latin America 1995 (PNUD 1996)

Similarly, Colombia identified in 1996 that, for sanitary actions in plant quarantines, Methyl Bromide was the only fumigant authorized for the treatment of fresh plant tissues at the ports of entry and exit and there is no other product as an alternative providing the required quarantine security. Consequently severe restriction and not total ban of the pesticide was adopted. However, taking into account what was identified by the panel of experts of the Montreal Protocol, it was required hermetic use with a closed pesticide recovery system.

Subsequently, some aspects to improve the fumigation process were identified to reduce the risk to the environment and health. Specifically, in 2008 the report on 'Use of Methyl Bromide for disinfection of aromatics for exporting" (Annex VII) carried out by the ICA, described the use of Methyl Bromide through fumigation with carps. However, it is important to note that this kind of fumigation generated concern in the aromatics union, since years before, due to possible emissions to the environment and workers exposure to the pesticide. Reason why in 2007 the ICA promoted meetings with the MAVDT to brief on the project 'Construction of two chambers for the commercial application of Methyl Bromide as quarantine treatment', as described on page 3 of Annex XI and Annex IX.

As a result of institutional, sectorial and inter-institutional work, resolution 5049 of 2008 was generated, modifying resolution 2152 of 1996, making the use of fumigation chambers for Methyl Bromide mandatory as expressed in the conclusions and commitments of the 27 August 2008 meeting of the inter-institutional working committee on the use of Methyl Bromide in Colombia (Annex XI and Annex IX).

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

Risk reduction of poisoning by the use of Methyl Bromide and contribute to the reduction of Methyl Bromide emissions that deplete the ozone layer, which increases solar radiation and in the long term may increase the risk of skin cancer in people.

Summary of known hazards and risks to the environment:

Methyl Bromide was included in the Montreal Protocol as an ozone layer depleting substance under the Copenhagen Amendment since this substance, upon reaching the stratosphere, photolyzes or reacts with OH and O and rapidly releases Bromine atoms. Unlike Chlorine, where only small fractions are reactive, Bromine is reactive for almost half of the total amount. Therefore, it is more efficient in catalytic ozone destruction than Chlorine. Furthermore, the photochemical gas phase separation between the reactive forms and reservoirs of bromine is quite rapid in sunlight, about one hour or less, such that the direct heterogeneous conversion of HBH and BroN02 to Bro is likely to have little impact on the bromine partition, except perhaps at polar twilight.

The mixing ratios of Nox, Hox and Clox increase strongly with an altitude above 20 km than with Bro and the fractional contribution to ozone loss due to Bromine is greater in the lower stratosphere. And it is there, where the concentrations of oxygen atoms are small, the Bro reaction is relatively insignificant, and the three reaction cycles listed below are mainly responsible for the Bromine-catalysed ozone loss, been Cycle III less important than Cycles I and II:

In the Polar Regions, where Nox is reduced and Clox is reinforced by heterogeneous reactions of sulphate aerosols and polar stratospheric clouds, the loss of ozone due to Bromine is evidenced in Cycle I. In mid-latitudes where the first two cycles occur, an approximately equal contribution of ozone loss is evidenced at 20 km. Cycle II occurs near the tropopause, where the abundance of H02 is substantial and the amount of Clox is negligible. Because Bromine is released more rapidly with altitude than Chlorine, and a fraction of inorganic Bromine remains in active forms, the catalytic destruction of ozone by Bromine is more important than Chlorine considering a mol-to-mol ratio.

As a consequence, at about 20 km the contribution of Bromine to the overall rate of ozone loss is almost as important as the contribution of Chlorine. However, the total ozone losses are the result of the continuous photochemical destruction of ozone that is generated when transporting from the region of origin in the tropics from lower altitudes to higher latitudes. Therefore, it is difficult to assess the overall contribution to ozone trends from instantaneous ozone loss rates (Annex V Chapter 10 pages 19 and 21).

As presented in section 2.4.2.1 Colombia identified the use of this pesticide in different crops, as well as the need to use it for quarantine treatment, reason why severe restriction of the pesticide through Resolution 2152 of 1996 was carried out. Later In 2008, more restrictions were implemented to control the use of Methyl Bromide and thus limiting this pesticide emission into the environment. Therefore, under Resolution 5049 of 2008, the use of hermetic fumigation chambers was made mandatory.

Expected effect of the final regulatory action in relation to the environment:

Reduction and control of emissions of ozone-depleting substances such as methyl bromide.

Date of entry into force of the final regulatory action: 12/12/2008