An Oct. 24 epidemiological study by Georgia Division of Public Health (DPH) left the door open but fell short of establishing a direct link to questions from hundreds of sick residents in Fayette and Fulton counties who believe the onion-like smell of chemical odorant propyl mercaptan released at the Philip Services Corp. (PSC) waste treatment plant in Fairburn is responsible for their illnesses. The door was also left open by a commitment for a larger state and federal health consultation expected by early 2007.

The Survey of Adverse Health Events concluded that the “release of propyl mercaptan at the PSC facility may have contributed to adverse health effects in some residents of communities around PSC, and for some residents has had a substantial negative impact of the quality of life.”

The report further concluded that exposure to the chemical at levels likely to occur outside an occupational setting is not known to cause long-term adverse health effects. That finding is consistent with chemical industry-generated material safety data sheets that almost exclusively state that long-term effects of exposure to propyl mercaptan and organophosphate pesticide MOCAP (ethroprop), also released at the plant, are unknown.

The study noted that EPD is continuing to monitor clean-up activities at the plant to eliminate residual ethroprop, the source of propyl mercaptan. The report cited PSC’s order to refuse any waste containing mercaptan, an order recently imposed by Fulton County in an amended pre-treatment permit set to expire Dec. 22.

The study’s final conclusion said that “if the plant operates within current guidelines and restrictions, it is in compliance with state and federal laws that protect the health of the public. We find no evidence the plant’s ongoing operations pose a health threat to the community.”

Relevant to affected residents but not part of the study conclusions were those symptoms reported during the months of May and early to mid-June, the same symptoms reported subsequent to the June 29 benchmark date of chemical emissions from the plant that formed the basis of the study. On June 29, PSC officials said four unacceptable loads of MOCAP “wash water” were rejected at the Fairburn waste processing plant after one load was temporarily off-loaded.

Apparently accepting the rationale of PSC and Georgia Environmental Protection Division (EPD), the DPH study did not account for the possibility that emissions escaped the plant when the first of 38 shipments of water wash reported by PSC arrived June 20.

“Many persons reported detecting the odor and experiencing symptom onset prior to the June 29 events reported by the PSC facility. Propyl mercaptan received and handled at the plant on June 29 could not have been the cause of adverse health effects before that date,” the report said.

Approximately 120 area residents reported at least two specified symptoms prior to the week of June 25, according to the study. Those symptoms included headache, burning eyes, cough or sore throat, nausea and vomiting, difficulty breathing, nosebleed, skin or eye irritation, abdominal cramping and diarrhea, slurred speech or dizziness, blood in urine, rapid pulse and elevated blood pressure.

To date, no study has been made or attempted with the Fayette/Fulton illnesses that would explain why so many residents detected the same odor prior to the mid-June date, with many reporting the the onion-like odor as far back as Memorial Day.

While careful not to draw a direct correlation between resident’s symptoms and emissions from the plant, the Fayette/Fulton study did cite a 1989 incident in Siskiyou County, California where propyl mercaptan was linked to similar symptoms exhibited by residents.

“These symptoms are nonspecific and neither the individual symptoms nor the case definition based on two or more of them can definitely implicate a specific source or exposure. However, the pattern of symptoms reported from late June through August is consistent with exposure to propyl mercaptan reportedly present at the PSC facility during that time. In 1989, persons from a California community exposed to propyl mercaptan following pesticide treatment of a nearby potato field reported similar symptoms,” the report said.

Another facet of the epidemiological study, the reported illnesses of 36 dogs and cats in communities near the PSC plant, found no consistent pattern of clinical signs that would suggest common exposure to a chemical toxin. The report included the factors that would account for the absence of chemical exposure but said nothing about the factors that have no clear explanation.

Without mention in the report, for example, were the deaths of three small dogs, all within a quarter-mile of the plant, that died within a few weeks of each other after exhibiting symptoms of difficulty breathing, losing hair, lethargy and refusing to eat. Two of the dogs were found bleeding from the nose and rectum.

Also without comment in the report were the deaths of four beehives just north of the plant and the absence of birds, butterflies and insects that normally inhabit the area during the summer months.

The study did note the concerns of some community residents over possible exposure to other chemicals processed at the plant. For many scores of residents, the June 29 benchmark date accepted by DPH and EPD is not sufficient to explain their illnesses.

“Some parts of the report are perplexing to me,” said Ga. Highway 92 resident Earl Hindman. “After looking at the MOCAP label I realize that my family and many others were experiencing symptoms of what seems like MOCAP poisoning much earlier than what the reports is saying. Or if it wasn’t MOCAP, then what was it?”

In response to those concerns, the DPH report said, “government officials are currently working to obtain and review information on shipments the facility received before that (June 29) date. In addition, in response to the propyl mercaptan release from the PSC facility and subsequent concerns about adverse health effects in the community, DPH has announced plans to conduct a Health Consultation in collaboration with the federal Agency for Toxic Substances and Disease Registry (ATSDR).”

That report is expected to be available for public review in late 2007 or early 2007.

State and federal officials in mid-September confirmed that tests showed a toxic chemical presence of hundreds of thousands of times the accepted upper safe exposure levels for humans in south Fulton County beginning in late spring and early summer.

“Based on results from environmental sampling, preliminary analysis of reported symptoms and the scientific data on the behavior of the chemicals involved, propyl mercaptan was released into the air at the PSC plant in late June and most likely caused symptoms reported in the community,” according to DPH Director Stuart Brown and EPD Director Carol Couch.

Compiling data from hundreds of residents in north and central Fayette and south Fulton counties, the DPH epidemiological study focused on exposure forms initially provided by Fayette County EMS.

The “Study of Adverse Health Events, Fairburn, Georgia and Neighboring Areas” can be found in the “Updates” section at www.health.state.ga.us/programs/hazards/index.asp.