The utilization of methyl bromide (MB) for quarantine purposes has been hampered by its designation as an ozone-depleting substance under the Montreal Protocol. The International Plant Protection Convention's (IPPC) call for alternatives to MB and a reduction in its usage. There is an urgent need to explore and implement substitutes. Despite some substitute agents like EDN being developed for wood, EDN has been limited due to various factors such as occupational risks. This study focuses on evaluating the efficacy of Sulfuryl Fluoride (SF) as a viable alternative fumigant against Reticulitermes speratus, one of major wood destroying pests. Experimental trials conducted at ambient temperature (23°C) revealed promising results, with SF demonstrating LCT50 and LCT99 values of 30.87 mg·h/L and 42.53 mg·h/L, respectively. Under low-temperature conditions (5°C), SF remained effective but with slightly higher LCT50 and LCT99 values of 151.62 mg·h/L and 401.90 mg·h/L, respectively. The penetration test, conducted using R. speratus-infested pine wood cubes, further highlighted SF's efficacy, with LCT50 and LCT99 values of 31.59 mg·h/L and 53.34mg·h/L at 23°C, indicating powerful penetration capabilities. When tested at a loading ratio of 90% (v/v) at 5.0mg/L for 24 hours in a 500L chamber as a middle-scale trial, SF achieved a 100% mortality, showing its potential as a suitable replacement for MB. These findings suggest that SF could open new markets as an MB substitute and enhance safety at quarantine sites when applied to imported and exported timber.
Research on alternative fumigants to replace methyl bromide (MB), a harmful ozone-depleting substance and highly toxic pesticide, began in 2007. Initial tests focused on using ethyl formate for fruits and EDN for wood. Subsequently, alternative techniques were developed for a total of 94 plant types using ethyl formate, EDN, and phosphine, demonstrating Korea's superior performance compared to other countries, especially in practical applications. However, when it comes to wood products, the primary users of methyl bromide, EDN is scarcely used due to concerns about worker safety. An emerging alternative to MB is sulfuryl fluoride (SF), widely employed in North America to control wood-damaging pests like termites. SF's advantages include a lower boiling point and higher vapor pressure, making it effective against wood pests. Yet, certain bark beetle eggs require higher doses and longer treatment periods, resulting in established international standards (e.g., 120g/m3 for 48 hours at 20℃), posing challenges for field applications. Recently, the APQA initiated basic research to apply SF to wood. They are assessing SF's effectiveness against various wood-destroying pests, including termites, bark beetles, and long horn beetles, while also evaluating the feasibility of mixed treatments to reduce dosage. Once SF fumigation standards are established, it is expected to significantly reduce methyl bromide use in commonly used wood types, contributing to ozone layer protection and enhancing fumigation work safety.
Methyl bromide (MB) has been still routinely used in quarantine fumigation on imported citrus, although there had been issuing chronic inhalation toxicity to fumigators and related workers as well as phytotoxic damages after fumigation. Ethyl formate (EF), is the only option to replace MB in terms of its safety for consumers (food additive and naturally occurred) and worker with higher threshold level limit (TLV = 100 ppm). Its application technology also provide cost effectiveness, good commercial practice in terms of application time (< 10 min) for 40 ft container. The replacement of MB with EF is recommended not to fumigate with hazardous and phasing-out MB on imported oranges.
To replace hazardous methyl bromide (MB) post-fumigation on imported fruits, due to insufficient ventilation process in industrial practice, alternative fumigation with liquid ethyl formate (EF) with N2 application, which is multi benefits to safe to workplace and environment, has been developed by APQA. Although EF was found to be shown proven efficacy to invasive external feeders such as mealybugs and scales on export and imported fruits and vegetables, there was still some conflicts to accept one of the phytosanitary disinfestation method somewhere because of on reliable and confirmative studies on between MB and EF in terms of efficacy to mealybugs on perishable commodities. In here, we evaluated comparative efficacy of EF and MB to target citrus mealybug, which was seems to be hard control pest, based on the current disinfestation guideline of them in Korea. The potential benefits of using liquid ethyl formate (EF) for future quarantine use could provide for safer workplace involved on and post-fumigation such as cold and packing storages, cost-effectiveness as well as meet the environmental friendly solution.
The existing ethyl formate fumigant is carbon dioxide (CO2) mixed liquified gas in metal cylinder, but this product type costs a lot to manufacture, translate and maintain cylinder. To supplement these problems, we have developed a new ethyl formate fumigation technique with nitrogen (N2) carrier. We assessed the susceptibility of mealy bugs, the most frequently detected pests in imported banana, and phytotoxicity of banana fruits. Ethyl formate and nitrogen were concurrently treated on citrus mealybug, one of the most resistant mealybug to fumigant, and ethyl formate was treated with LC50 product of independent treatment dosage. Nitrogen was treated with 7 dosages from 79% to 95% concentration. Phytotoxicity of banana was assessed by treating EF 35 mg/L with N2 79% for 14 days, and color, sugar contents and loss of weight were measured. EF with N2 treatment showed more than 50% of mortality on every growth stages, and there was no significant difference between control and treatment banana fruits. These results indicate that concurrent treatment of EF and N2 can be used to control mealybug in banana fruits.
알락하늘소(Anoplophora chinensis)와 유리알락하늘소(A. glabripennis)는 전 세계적으로 검역상 중요한 하늘소과 해충이다. 우리나라에서 이들은 자연 기주목과 분재에서 피해를 주고 있다. 본 연구에서는 분재에서 phosphine의 이들 두 하늘소에 대한 방제효과를 조사하였다. Phosphine은 솔수염하늘소 유충과 알에 대해 높은 훈증효과를 보였다. 2 g/m3 농도의 phosphine을 24시간 훈증처리 시 유리알락하늘소와 알락하늘소 난은 부화하지 못하였고, 알락하늘소 유충은 동일농도에 168시간 훈증처리 시 100% 치사되었다. 분재 생육기(2월)나 휴면기(1월) 모두에서 phosphine 훈증제는 2 g/m3 농도에서 두 알락하늘소를 100% 치사시켰다. 그러나 2월에 각 분재목[단풍나무(Acer palmatum)와 소사나무(Carpinus turczaninowii), 아그배나무(Malus sieboldii)]을 대상으로 훈증처리 시, 세 수종 모두에서 잎과 꽃잎의 크기가 작아지고, 꽃의 개화가 지연되는 약해가 발생되었다.
Exportation of sweet persimmon has been grown up recently, but the growth was accumulated because of quarantine and shelf life issues. Herein, we've investigated the concurrent processing of ethyl formate (EtF), a MeBr alternative quarantine fumigant, and 1-methylcyclopropene (1-MCP), an anti-ethylene compound, on sweet persimmon and suggested proper fumigation methods. An important quarantine pest, Tetranychus urticae, was inoculated on sweet persimmon, and then 70 g m-3 of ethyl formate has been fumigated for 6 h before and after 1 ppm of 1-MCP treatment for 24 h at 5°C condition. These concurrent processing showed the promise that efficacy of EtF was enough to meet quarantine guideline and shelf life of fruits was extended in terms of the hardness, surface color and sugar contents when treated fruits were stored for four weeks at 5°C.
Methyl bromide (MB) fumigation is still allowed to use in quarantine treatment on imported timbers and logs, even though IPPC(International Plant Protection Convention) was strongly recommended to reduce their use in case of existing alternatives. A newly developing MB alternative fumigant, ethanedinitrile (EDN), showed the potential in terms of better efficacy to various timber pests and penetration into the timber than MB. Herein, for suggestion of quarantine guideline in Korea, we had verified the efficacies under different temperature conditions(5, 5-15, >15℃) and monitored TLV(Threshold limited value) of EDN post-fumigation for worker safety. The 6 scheduled doses of EDN depending on types of timber pest and temperature conditions had evaluated with PVC-Tarp tent(>100m3) with 40-50% loading factors of imported logs. To control normal wood related pests such as Japanese termite (Reticulitermes speratus) and bark beetle(Cryphalus fulvus), the scheduled doses 30, 40 and 40 g/m3 for 24hr fumigations showed >99% efficacy at 5, 5-15 and >15℃, respectively. The scheduled doses 100, 120 and 150 g/m3 for 24hr fumigations was also successful to gain the proved efficacies at 5, 5-15, >15℃, respectively, for the quarantine guideline to notorious wood related pests such as Japanese pine sawyer (Monochamus alternatus) and pine wilt nematode (Bursaphelenchus xylophilus). The recommended ventilation times with atmospheric conditions at ports was > 1 and > 2 hr under the fully uncovered and partially uncovered of fumigation tent conditions, respectively.
With the increasing trend of global trades and protection of agro-ecosystem in importing and exporting countries, quarantine and pre-shipment(QPS) fumigation for perishable commodities are critical in terms of quality maintenance of fumigated commodities as well as eradicating quarantine pest. There are limited use of methyl bromide(MB) fumigation on fruits and vegetables due to not only worker safety issue at low temperature condition but phytotoxic damage to valuable commodities. We are here presented that commercial development of methyl bromide (MB) alternatives such as ethyl formate and phosphine gas formulated with carbon dioxide, that are increasing consumer and worker safety and avoiding phytotoxic damage in routine MB fumigation.
Methyl Bromide (MB) has been regulated by montreal protocol due to ozone depletion since 1992, and there is a need to develop MB alternative fumigation methods. To find out the efficacies and tolerance in developmental stages of citrus mealybugs (Planococcus citri) which frequently infested in imported pineapples, phosphine(PH3) gas was tested in different exposure times (2~24 hr) and concentrations (0.1∼2g/m3) in small desiccators at 8℃. Based on Lethal 99% concentration × time products (LCTP 99%) of PH3 gas to target developmental insect, 2g/m3 PH3 was applied for 24 hr in 300 m3 fumigation facility, which was designed in well sealed and evacuation system (5 air exchange/min). We monitored PH3 gas in fumigation facility to confirm CTP and checked PH3 gas in atmospheres in air ventiliation process after fumigations to make quarantine guideline and protocol for worker safety as well as efficacy to target pest.
Methyl bromide (MB) has been banned by Montreal Protocol due to ozone depletion in developed countries since 2005 but uses for quarantine & pre-shipment (QPS) remains exemption due to no appropriate alternatives yet available. However, in 2010, the prohibition of QPS in European Union(EU) will be expected to phase out MB worldwide use. There is an inevitable need for MB alternatives technology. Also, other consumer's demand in QPS is that MB has damaging effect to the quality of highly valuable fresh products: some fruits, vegetables and mostly cut flowers. We evaluated 2% of phosphine(PH3) and 98% of CO2 mixtures as MB alternative in export cut flower fumigation. On sensitivity test, larvae of Aphis gossypii were most tolerant to PH3 fumigation in all stage of A. gossypii, Tetranychus urticae and Frankliniella occidentalis. The LC99 and LCT99 value of mixture gas for larvae of A. gossypii was 55 mg/L (24hr, 15℃) and 1,224 mgh/L(15℃), respectively. On confirmation trials scheduled in 28m3 container, all stages of A. gossypii, T. urticae, and F. occidentalis were completely controlled in 100g/㎥ of mixture gas for 24hrs at 8℃, and no damage was observed in roses, chrysanthemums, and lilies. The PH3 and CO2 mixture technology in cut flowers fumigation and their application will plays an practically important roles in further MB replacement strategy in Korea.