**UNITED STATES ENVIRONMENTAL PROTECTION AGENCY**

**WASHINGTON, D.C. 20460**

![](media/image1.png){width="5.330555555555556in"
height="0.4777777777777778in"}

April 18, 2006

**[MEMORANDUM]{.underline}**

**SUBJECT:** Incident Reports Associated with
2-(Thiocyanomethylthio)benzothiazole (TCMTB)

**TO:** Kathryn Avivah Jakob, Chemical Review Manager

Mark Hartman, Branch Chief

Regulatory Management Branch II

Antimicrobials Division (7510C)

**FROM:** Jonathan Chen,

Risk Assessment and Science Support Branch

Antimicrobials Division (7510C)

**THRU:** Norm Cook, Branch Chief

Risk Assessment and Science Support Branch

Antimicrobials Division (7510C)

**PC Code:** 035603 **Decision Number:** 361478 **Data Package Number:**
(328526)

# 1.0 INTRODUCTION

The chemical 2-(Thiocyanomethylthio) benzothiazole (TCMTB) was first
registered with the EPA on January 21, 1980. As an antimicrobial
pesticide, TCMTB is used largely as a wood preservative. It is also used
as a microbiocide/microbiostat and bacteriocide/bacteriostat in
industrial processes and water systems, as well as in industrial
materials as a preservative. As an agricultural pesticide TCMTB is used
for seed treatment of crops, bulbs, and corn as well as treatment of
flowers and seed and soil treatment of trees. The purpose of this
chapter is to review the evidence of health effects in humans resulting
from exposure to TCMTB.

Two approaches are used in this section:

1.  The potential health effects of TCMTB in humans, reported as
    incident reports from different sources, are summarized.

2.  A literature search of chronic health effects associated with TCMTB
    exposure, including results of epidemiological studies, is
    summarized.

# 2.0 INCIDENT REPORT DATA ASSOCIATED WITH HEALTH EFFECTS 

The following databases have been consulted for the poisoning incident
data:

**[OPP Incident Data System (IDS)]{.underline}** - The Incident Data
System of The Office of Pesticide Programs (OPP) of the Environmental
Protection Agency (EPA) contains reports of incidents from various
sources, including registrants, other federal and state health and
environmental agencies and individual consumers, submitted to OPP since
1992. Reports submitted to the Incident Data System represent anecdotal
reports or allegations only, unless otherwise stated. Typically no
conclusions can be drawn implicating the pesticide as a cause of any of
the reported health effects. Nevertheless, sometimes with enough cases
and/or enough documentation, risk mitigation measures may be suggested.

**[Poison Control Centers]{.underline}** - as the result of a data
purchase by EPA, OPP received Poison Control Center data covering the
years 1993 through 2003 for all pesticides. Most of the national Poison
Control Centers (PCCs) participate in a national data collection system,
the Toxic Exposure Surveillance System, which obtains data from about
65-70 centers at hospitals and universities. PCCs provide telephone
consultation for individuals and health care providers on suspected
poisonings involving drugs, household products, pesticides, etc.

**[California Department of Pesticide Regulation]{.underline}** -
California has collected uniform data on suspected pesticide poisonings
since 1982. Physicians are required, by statute, to report to their
local health officer all occurrences of illness suspected of being
related to exposure to pesticides. The majority of the incidents involve
workers. Information on exposure (worker activity), type of illness
(systemic, eye, skin, eye/skin and respiratory), likelihood of a causal
relationship, and number of days off work and in the hospital are
provided.

**[National Pesticide Telecommunications Network (NPTN)]{.underline}** -
NPTN is a toll-free information service supported by OPP. A ranking of
the top 200 active ingredients for which telephone calls were received
during calendar years 1984-1991, inclusive, has been prepared. The total
number of calls was tabulated for the categories human incidents, animal
incidents, calls for information, and others.

**[Published Incident Reports]{.underline}** - Some incident reports
associated with TCMTB related human health hazards are published in the
scientific literature.

## 2.1 [OPP=s Incident Data System (IDS)]{.underline}

There are 21 incidences that have been reported in the OPP incident data
system that are associated with TCMTB exposure.

The most common symptoms reported for cases of dermal exposure were skin
irritation/burning, rash, itching, skin discoloration/redness, and
blistering.

The most common symptoms reported for cases of inhalation exposure were
respiratory irritation/burning, irritation to mouth/throat/nose,
coughing/choking, shortness of breath, and sore throat.

There were three incidences that involved ingestion exposure to TCMTB,
and the reported symptoms included irritation to mouth/throat/nose,
abdominal pain, kidney failure, hypothermia and loss of consciousness.

## 2.2 [Poison Control Center (1993 -- 2003)]{.underline}

There is no reported TCMTB specific incident in the PCC's database.

## 2.3 [California Data - 1982 through 2003]{.underline}

There are 4 incidences that have been reported in the California
Pesticide Surveillance Program Database (1982-2003) as possibly or
probably TCMTB related (Mehler, 2005). The descriptions of the four
incidences are listed below. .

Case 1982-1631 concerns a man who filled new bags with treated seed,
sewed the bags shut, and stacked them. The day was very hot (temperature
higher than 100 degrees), and he worked without a shirt. Two of the four
workers doing this task developed rashes for which they sought medical
advice. This worker\'s condition was described as \"Rash, difficulty
breathing, redness of arms, face, shoulders, feet, and his hair also
turned purple.\" The worker developed \"peeling and redness of both
forearms\" and a \"mild bronchitis\", and he was off work for a week.

Cases 1985-231 and 233 both occurred at a lumber planning mill, which
had recently and inadequately installed equipment to treat their
products with fungicide to reduce sapstain. The installation allowed
back flow into the potable water supply, but no workers drank it because
excessive iron levels had long made the water unpalatable. They drank
bottled water. We do not know how they were exposed. A total of 103
employees were evaluated for the exposure, most of them asymptomatic so
far as we know. The subject of case 1985-231 noticed blood in his urine
(not present at time of examination). The subject of case 1985-233
developed a rash on her chest and back.

Case 1989-2417 concerns a loader for an aerial applicator who had loaded
nothing but treated wheat seed. He had no problems during his first nine
days on the job, but on the tenth day he cleaned the aircraft with a
solvent and developed an itchy rash on his hands and forearms. The
investigation points out that the solvent seems the more likely cause,
but we could not rule out a contribution from the seed treatment.

## 2.4 [National Pesticide Telecommunications Network (NPTN)]{.underline}

There is no incident reported in the NPTN database related to TCMTB
exposure.

## 2.5 [Incident Reports / Epidemiological Studies Published in Scientific Literature.]{.underline}

A cross-sectional study was conducted to study the health effects
associated with the use of TCMTB in the British Columbia sawmill
industry (Teschke, 1992). Workers in five costal sawmills were asked to
complete a self-administered questionnaire about symptoms considered
potentially related and unrelated to fungicide exposure, and about
injuries commonly reported in sawmills. The reported symptoms
consistently found to be related to TCMTB mills included dry skin around
the eyes, blood-stained mucus from the nose, nose bleed, peeling skin,
burning or itching skin, and skin redness or rash.

# 3.0 EPIDEMIOLOGICAL DATA ASSOCIATED WITH CHRONIC HEALTH EFFECTS

There is no epidemiological data that can be located associated with the
chronic health effects of TCMTB exposure.

# 4.0 SUMMARY AND CONCLUSION

There are incidences that have been reported associated with exposure to
end-use products containing TCMTB. Dermal and inhalation are the primary
routes of exposure. Most of the incidences are related to irritation
type reactions.

The most common symptoms reported for cases of dermal exposure were skin
irritation/burning, rash, itching, skin discoloration/redness and
blistering.

The most common symptoms reported for cases of ocular exposure were eye
irritation/burning. Eye pain and swelling of the eyes has also been
reported in some instances.

The most common symptoms reported for cases of inhalation exposure were
respiratory irritation/burning, irritation to mouth/throat/nose,
coughing/choking, shortness of breath, and sore throat.

Although oral exposure is considered to be a minor route of exposure for
TCMTB use, irritation to mouth/throat/nose, abdominal pain, kidney
failure, hypothermia and loss of consciousness were reported in cases of
ingestion.

# REFERENCE

Mehler, L. 2003. Personal Communication. California Department of
Pesticide Regulation.

Teschke, K.; Hertzman, C.; Wlena, M.; Dimich-Ward, H.; Hershier, R.;
Ostry, A.; and Kelly, S.J. 1992. Recognizing Acute Health Effects of
Substitute Fungicides: Are First-Aid Reports Effective? American Journal
of Industrial Medicine 21: 375-382.