Laboratory evaluation of large-scale decontamination approaches

Abstract

Aims: To evaluate the effectiveness of two spray‐based decontamination methods for surface contamination reduction and to determine the potential for contamination spread by these methods. Methods and Results: Material coupons (treated plywood and concrete) were contaminated with c. 1 × 107 spores of Bacillus atrophaeus by aerosol deposition. Decontaminants (pH‐adjusted bleach or Spor‐Klenz® RTU) were applied to coupons by either backpack sprayer or gas‐powered sprayer. Contact time, reapplication frequency and rinse method were also varied. In addition to surface removal efficacy, partitioning of contamination between the rinsate and aerosol fractions was determined. Results indicated that pH‐adjusted bleach was effective (≥6 logs reduction) when two applications and a 30 min contact time were administered, regardless of the decontaminant application method or material. Spor‐Klenz® RTU was effective on wood, but achieved ≤3 logs reduction on concrete. A shortened application procedure with pH‐adjusted bleach resulted in lower efficacy on wood, and a greater apparent potential for contamination spread. Conclusions: Consideration of material surface type is important when selecting a decontaminant. Also, achieving conditions that effectively inactivate surface biological contamination are critical to preventing the spread of contamination. Significance and Impact of the Study: Results presented here are intended to help development of remediation plans following a biological contamination incident.

Evaluation of standardized sample collection, packaging, and decontamination procedures to assess cross-contamination potential duringBacillus anthracisincident response operations

“…Recovery data are reported as Log 10 CFU, decontamination efficacy data are reported as Log Reduction in total recovery (Log 10 positive controls – Log 10 experimental), and were reduced as described previously. [31] Statistical significance was assessed using a p-value threshold of 0.05.…”

Decontamination of High-risk Animal and Zoonotic Pathogens

“…Therefore, several technical reports were published by the US Environmental Protection Agency (EPA) assessing different means and procedures for indoor and outdoor decontamination and accounting for ecological and economical aspects. [55][56][57][58][59][60] Hydrogen peroxide and peracetic acid products as well as hypochlorous substances were found to be efficient, 56,60 as were bleach and chlorine dioxide, which showed inactivating results for B. anthracis spores. 55,56,[58][59][60] The EPA reports are valuable for animal health and for public health issues.…”

Decontamination Condition of Geobacillus Stearothermophilus Spore on the Surface of Various Coupons using Hydrogen Peroxide Vapor

“…생물학적 제독이란 장비나 건물과 같은 무생물인 대 †2013년 5월 18일 접수～2013년 7월 26일 게재승인 * 한양대학교 ** 삼양화학공업(주) *** 국방과학연구소(ADD) 책임저자 : 채영규(ygchai@hanyang.ac.kr) 상으로부터 미생물들을 제거하고, 이를 통해 그 대상 을 다시 사용하거나 혹은 안전한 상태에서 폐기가 가 능하게 하는 것을 말한다 [1] . 2001년 미국에서 일어난 탄저균 테러 이후로 많은 제독 방법들이 개발이 되어 왔고, 특히 오염된 시설 및 장비에 의한 2차 감염과 경제적 손실 등을 최소화하기 위한 높은 효율성을 가 진 제독제를 위한 연구가 이루어지고 있다 [2] .…”