This section includes a discussion of environmental contaminants of health concern. Appendix A contains additional details, including background concentrations (Table A1, Appendix A). Contaminants of health concern are selected after consideration of the following criteria:
- concentrations of contaminants in environmental media, such as soil and water;
- quality of the samples, the laboratory analyses, and the sampling design;
- comparison of the contaminant concentrations with background concentrations, if available;
- comparison of the contaminant concentrations with comparison values(2); and
- community health concerns.
The inclusion of a contaminant in the list of contaminants of concern does not necessarily indicate that the contaminant will cause adverse health effects. Instead, this list indicates contaminants that will be evaluated further in this public health assessment to determine whether exposure to them is occurring and whether that exposure may be of significance to public health. Also, some substances may be included on the list of contaminants of concern which are not site-related. This may happen when a contaminant is naturally present at high concentrations, or when there is no information about the natural, or background, concentration.
The major contaminants at the Reynolds site are aluminum, fluoride, and polynuclear aromatic hydrocarbons, or PAHs. The PAHs come mainly from coal-tars and carbon blocks that were used in aluminum processing. The aluminum and fluoride are mainly in the form of aluminum oxide and cryolite, which is sodium aluminum fluoride. Cryolite does not dissolve well in water, and so the aluminum and fluoride which have contaminated soils in the area have not washed away. Polychlorinated biphenyls, or PCBs, are also frequent contaminants at this site. PCBs were used in transformers, which have been used at the Reynolds facility.
A. ON-SITE CONTAMINATION
Soils on the Reynolds site are generally contaminated with aluminum, fluoride, and PAHs (Table A2, Appendix A). Soils also occasionally contain arsenic, PCBs, mercury, and antimony. Chromium and nickel were also found in the scrap yard. Free mercury was found in soil in the scrap yard in April 1992. Concentrations of mercury in soils in this area were very high and remain moderately elevated after removal of the mercury and much of the contaminated soils.
Soils in the north landfill near the Columbia River are contaminated with aluminum, mercury, PAHs, and PCBs. In addition, an asbestos cloth was found within the landfill during the soil sampling.
Soils in the wetland to the south of the plant are contaminated with PAHs and PCBs. Mercury was observed at a low concentration in one of the five soil samples.
Sediments across the site were contaminated with aluminum and PAHs (Table A3, Appendix A). Most also had high concentrations of fluoride. Mercury was observed in sediments in the wetlands and in the outfall leading from Company Lake to the Columbia River. Arsenic was frequently observed. The pesticide DDT and related compounds were observed in wetlands sediments. Thallium was found in Company Lake sediments.
Water in Salmon Creek, East Lake, Company Lake and South Ditch were sampled and analyzed for contamination (Table A4, Appendix A). Aluminum was present in all samples except those from East Lake, which contained only lead and fluoride. Company Lake waters were also contaminated with fluoride, and water in its outfall ditch was contaminated with arsenic and PAHs.
Groundwater in the area of the Reynolds Metals Company occurs in an unconfined aquifer(3). Groundwater is relatively shallow and can be reached at depths ranging from 5 to 18 feet below the ground. Sixteen monitoring wells(4) were constructed on the Reynolds Metals site. These wells were designed to collect groundwater from shallow depths, with the deepest well extending down to 30 feet below the ground. Groundwater from these wells contained aluminum, fluoride, mercury, arsenic, several other metals, and cyanide (Table A5, Appendix A). In addition, 1,1-dichloroethane was observed in groundwater near the north landfill, which is near the Columbia and Sandy rivers. 1,4-Dichlorobenzene was observed in groundwater between the Reynolds facility and the Sandy River.
Analysis of the level of the shallow groundwater in the monitoring wells indicated that groundwater tends to flow to the north or northwest. Groundwater in the vicinity of the Sandy River flows northeast, directly toward the river. There was also a depression in the groundwater levels in the area of Production Well 15, which was no longer in use [CH2M Hill, 1994]. This could indicate that shallow groundwater was flowing down the casing of well 15 into the deeper groundwater, in which case the deeper groundwater could have become contaminated. To end this possibility, Production Well 15 was properly abandoned(5) in March 1995. Since then it was determined that the depression was unrelated to the presence of the former production well.
Groundwater from five on-site production wells was also analyzed for contamination. The production wells draw water from much deeper levels than did the monitoring wells. They extend from 180 to 590 feet below ground. Groundwater from these wells contained aluminum, arsenic, mercury, and fluoride. The concentration of these contaminants was in each case smaller than the concentration seen in the shallow groundwater.
B. OFF-SITE CONTAMINATION
Fairview Farm is west of the Reynolds Metals Company facility. Although Reynolds owns the farm, it is considered an off-site area for this document. Two soil samples were taken from drainage soils on Fairview Farms and were found to contain PAHs and aluminum (Table A6, Appendix A).
Sediment samples from the Columbia River were collected near the shore bordering the Reynolds site. One sample was taken from an area 100 feet upstream of the Company Lake outfall and another from 200 feet downstream of the outfall. Although PAHs and aluminum were observed in these samples, they were present at concentrations similar to those in sediments from several miles upstream in the Columbia River (Table A7, Appendix A), indicating that the presence of PAHs and aluminum in the Columbia River sediments may not be related to the site.
Water from the Columbia River was collected 100 feet upstream of the Company Lake outfall, near the shore bordering the Reynolds site. Since this location is upstream of the outfall, this data may not represent the effect that the outfall discharge may have on the quality of the river water, although the Columbia River is subject to tidal influences at this point. Aluminum was observed in this sample, but was not detected in a similar sample collected several miles upstream in the Columbia River within the NPDES permitted mixing zone (Table A8, Appendix A).
Fish in the Columbia River
The Lower Columbia River Bi-State Program has sampled fish from the Columbia River for mercury, PAHs, and PCBs (Table A9, Appendix A). These contaminants are of concern in fish throughout the Columbia River as a result of many possible sources; the Reynolds Metals Company is only one of these possible sources. The data which will be discussed are from fish in the vicinity of Reynolds Metals, although the contamination of fish in this area does not differ from that of fish throughout the river. Mercury was frequently found in the fish tissues, up to a concentration of 0.2 micrograms per gram (µg/g) in the area near Reynolds Metals. Among PAHs, only naphthalene and 2-methyl naphthalene were found, and only in a very few fish. PCBs were detected in about half the fish, with a maximum concentration in the area near the Reynolds site of approximately 120 µg/g. These levels of contaminants in fish caught near the Reynolds facility do not differ from those of fish throughout the Columbia, or from those observed in fish nationwide [ATSDR, 1993b, 1993c, and 1994, and HSDB, 1996].
Groundwater - Private Wells
Groundwater from three private wells was sampled and analyzed for contamination. These wells were chosen because they are down gradient of the Reynolds Metals site. One well, on Fairview Farms, is used for irrigation. The others are used for drinking and process water. The wells range in depth from 119 to 233 feet below ground, so that they draw water from the deeper groundwater, and not from the more contaminated shallow groundwater(6). No contamination was found in the groundwater from these wells, although the analyses did not include evaluations for aluminum.
To determine whether nearby residents and workers are exposed to contaminants migrating from the site, ATSDR evaluates the scenarios that may lead to human exposure--the exposure pathways.
ATSDR categorizes an exposure pathway as either completed or potential. Completed pathways indicate that exposure to a contaminant has occurred in the past, is occurring, or will occur in the future. Potential pathways indicate that exposure to a contaminant could have occurred in the past, could be occurring, or could occur in the future. The discussion that follows incorporates only those pathways that are important and relevant to the site.
A. COMPLETED EXPOSURE PATHWAYS
Boaters who land their boats on the shoreline and people who come to fish and to pick blackberries frequently visit the area between the Reynolds Metals industrial facility and the Columbia River. This area contains the north landfill, East Lake, and Company Lake and its outfall. People who visit the area could become exposed to contamination in soils and sediments by hiking or wading. They might accidentally ingest small amounts of soil or sediment, either through inhalation of dust particles or by getting contaminated soils or sediments onto their hands and then eating, drinking, or smoking. These hand-to-mouth activities may transfer some of the contaminated soil to the mouth, where it is then swallowed.
It is not known how many people may be affected by exposure to contamination through this pathway. However, ATSDR's estimate is that up to 500 people may visit the area for recreational purposes.
People Who Eat Fish From the Columbia River
Contaminated soils, sediments, groundwater, and surface water at the Reynolds Metals site may potentially migrate into the Columbia and Sandy rivers. This potential has been realized to a small extent in the elevated aluminum concentration present in river water near the Company Lake outfall. A few of the site contaminants can be absorbed by and concentrated in fish, if those contaminants reach either the Sandy or Columbia Rivers. Contaminants most likely to concentrate in fish are mercury and PCBs, and, to a lesser extent, fluoride and PAHs. Many of the species of fish in the Columbia River are migratory and so would spend only a portion of their lifetimes in the area of the Reynolds site. This limited time exposure would tend to decrease significantly the amount of contamination the fish may absorb from the site. On the other hand, there are several other sources for these contaminants along the Columbia River, which can increase the amount of total contamination which fish may absorb.
Fish in the Columbia River have been contaminated by mercury, PAHs, and PCBs. The Reynolds Metals site may have contributed to this contamination, although it is difficult to determine the extent of its contribution. The Columbia River supports both commercial and recreational fishing. People who eat fish from the river may be exposed to the contaminants from the river. It is difficult to estimate the number of people affected.
Workers at the Reynolds Facility
Employees at the facility are likely to be exposed to contamination in on-site soils and sediments while at work. They may contact these soils and absorb some contaminants through their skin, and accidentally ingest small amounts of soil by inhaling the particles as dust when working outside or by getting contaminated soils onto their hands and transferring them to their mouths through eating, drinking, or smoking. Employees at the facility are not likely to be exposed to contamination in on-site production wells, because of bottled drinking water.
The 100 employees who currently work at the facility may be affected. When the plant was reducing aluminum ore, it employed up to 950 people. There are plans to resume full operation in the near future, which would increase the number of employees [personal communication, Steve Shaw, Reynolds Metals Co.].
B. POTENTIAL EXPOSURE PATHWAYS
In its early operations, the facility released large quantities of particulates into the air. These particulates were probably composed of PAHs, aluminum, and fluoride. No air sampling was done at that time. The amount of wastes which were released into the air was greatly reduced in 1950, when better waste control systems were installed. One family who had lived a mile to a mile and a half from the site prior to 1950 won a lawsuit filed against the Reynolds Metals Company for "damage to persons ... from 'excessive amounts' of fluorides [Reynolds v Yturbide]." The family produced medical testimony which "did connect their disabilities and physical injuries with the fluorides escaping from the plant [Reynolds v Yturbide]." In addition, they indicated that "their abnormal symptoms were reduced and lessened after they had moved away from the vicinity of the plant [Reynolds v Yturbide]." However, no detail about what their symptoms may have been is given, making it difficult to determine the extent of the family's exposure.
After 1950, the plant released much smaller amounts of particulates into the air. The amounts which have been released since then are not expected to cause adverse health effects from breathing the air in the vicinity of the plant.
Nineteen off-site, private wells have been identified within one mile of the Reynolds facility. These wells are used for drinking water and process water and for the irrigation of crops. Three of these wells were identified as the most vulnerable to contamination because they were the closest wells down gradient from the site. When these three wells were sampled, no contamination was observed, indicating that people using these wells are not being exposed to those contaminants investigated. However, the analyses did not include tests for aluminum, which is a major contaminant at this site. There is also potential for these wells to become contaminated in the future.
Blackberries grow in abundance in the area near Company and East lakes. People visiting the area pick and eat the berries. Blackberries may have the potential to absorb PAHs and fluoride, both of which are found in high concentrations in soils in this area. However, no sampling of the blackberries has been done to determine whether they might absorb these contaminants, and so no determination can be made regarding the health effects of eating these berries.
Beef cattle at Fairview Farms were watered from the Salmon Creek, which drains the wetlands south of the Reynolds facility. Contamination currently found in wetlands sediments includes PAHs and PCBs. Had they been transported to the cattle through Salmon Creek, these substances may have been absorbed by the cattle, possibly exposing people who consume beef from the cattle to PAHs and PCBs. However, there is little information regarding the absorption by and distribution of PAHs and PCBs in beef cattle. Although these cattle could also have been exposed to aluminum and fluoride in airborne dust generated by the plant, little exposure is expected to occur to people eating the beef, because aluminum and fluoride do not accumulate in muscle tissue.
PUBLIC HEALTH IMPLICATIONS
This section evaluates the possible effects that contamination from the Reynolds Metals Company site may have on public health. The toxicological evidence for adverse health effects caused by the site contaminants will be considered first. If then it is determined that adverse health effects are possible, available information will be considered regarding the health of the local population. This is done to determine whether any of the possible effects may be observed through epidemiological data.
A. TOXICOLOGICAL EVALUATION
This section contains a discussion of contaminants to which people are exposed and which may cause adverse effects. Toxicological information about the contaminants will be evaluated to determine what types of adverse health effects are possible, given the concentrations found at this site, and the ways in which people are exposed to the contamination. The evaluation reflects consideration of the strength of the evidence for each possible effect. Appendix B contains additional information about significant contaminants.
People who visit the area bordering the Columbia River for recreational purposes may be exposed to contaminated soils and sediments while hiking or wading in the area. They might accidentally ingest small amounts of these soils and sediments each time they visit the area. In addition, some of the site contaminants may be absorbed through the skin. This group of people can include children, who tend to swallow more soil accidentally than adults do. Children are assumed to ingest 200 milligrams (mg) of soil every day. Very young children may swallow much more soil, and are more likely to swallow surface water. However, it is unlikely that children this young would be present in this area. For this assessment, recreational users are assumed to visit the area monthly and to wade in Company Lake or its outfall ditch on three of those visits each year. People who have greater exposure than is assumed would have a greater potential for ill effects.
Recreational users can become exposed to aluminum and fluoride, PAHs, PCBs, arsenic, mercury, and possibly thallium in the soils and sediments in this area. Based upon the exposure scenario for this group, they should experience no increased risk of developing cancer, or of experiencing other adverse health effects. However, should children visit the area and wade in the lake and ditch more often than monthly, they may become exposed to enough fluoride to affect their bones and teeth.
People are also exposed to fluoride from fluoridated toothpaste and mouthwash, particularly small children, who do not have complete control of their swallowing reflex. They may accidentally ingest about 0.1 mg of fluoride each time they brush their teeth, and 0.3 mg each time they use a fluoridated mouthwash. Although this small amount of fluoride may be beneficial to a child by decreasing the incidence of tooth decay, it adds to what the child has otherwise been exposed to, resulting in a higher total dose of fluoride, and a greater risk of developing harmful effects.
Exposure to fluoride at high amounts for a long period of time can affect the bones and teeth. When a child is exposed during the development of the permanent teeth, the teeth can become mottled or stained. High levels of fluoride can also cause an increase in the development of dental cavities. The bones also absorb fluoride. When this occurs at high levels for several years, it can result in decreased amounts of calcium in the bone and a thickening and weakening of the bones. This causes an increased risk for bone fractures.
The body eliminates fluoride quickly, and bone absorbs fluoride slowly. Therefore, a person must be exposed to fluoride over a long period of time before effects may appear. Therefore, the infrequent exposure of most recreational users would not result in adverse effects. More frequent exposures, on the other hand, could cause effects to the bones and teeth.
People Who Eat Fish From the Columbia River
Fish in the Columbia River near the Reynolds Metals site are contaminated with mercury, PAHs, and PCBs at levels which are similar to those throughout the Columbia River and throughout the US. The Reynolds site may have contributed to this contamination, although it is difficult to determine the extent of its contribution. People who eat fish caught from the Columbia River in this area may be exposed to this contamination, although the level of exposure would not differ from that caused by eating fish from other sources. It is assumed that these people may eat a fish meal, consisting of a quarter pound of fish flesh, four times a week. Based on this amount of fish consumption, no adverse health effects are expected from the mercury and PAHs (naphthalene and 2-methyl naphthalene).
PCBs have been found to cause liver cancer in animals after the animals were exposed to them by eating contaminated food or drinking contaminated water. There is no evidence that PCBs have this effect on people. However, should PCBs be capable of causing cancer in people, the risk of developing cancer after eating fish caught in this area is probably very small, and is no different from the risk which is experienced nationwide.
Workers at the Reynolds Facility
Workers at the Reynolds facility are likely to be exposed to contamination in on-site soils, sediments, and groundwater while at work. They may accidentally ingest small amounts of soils contaminated with aluminum and fluoride, PAHs, PCBs, arsenic, mercury, and possibly thallium and DDT-related compounds. They are assumed to ingest as much as 100 mg of soil a day.
There are three main exposure scenarios for workers at the site. The first includes workers who are exposed only to the contaminated groundwater. The second involves machine and process workers who drink the groundwater and might receive only occasional exposure to contaminated soils and sediments. This exposure would be in addition to occupational exposures they might receive through the inhalation of fumes in the process and loading areas. Occupational exposures are beyond the scope of this public health assessment. The third exposure scenario is associated with ground workers, including maintenance staff members and any construction or remedial workers who are exposed to contaminated soils, sediments, and groundwater. For the purposes of this health assessment, assumptions are made regarding workers' exposure to contaminated materials. Their actual exposure, however, is dependent on many factors, such as workplace conditions, work practices, and personal protection measures, which have not been evaluated. People who have duties that result in additional exposures to any of these contaminants are at greater risk than this study has discussed.
All workers at the Reynolds facility are likely to be exposed to aluminum, fluoride, and arsenic in drinking water. However, the amounts that they are exposed to by drinking the water are not large enough to cause any adverse health effects.
Machine and process workers may be exposed on occasion to contaminated soils, although their exposure is most likely very infrequent and is not expected to cause any adverse health effects. They could also be exposed to similar substances occupationally.
Ground workers are likely to be exposed to contaminated soils and sediments more frequently. They are assumed to visit the most contaminated areas, usually the area near Company Lake, once a week, and to contact sediments in Company Lake or the wetlands once a month. Based on the amounts of contaminants that workers would be exposed to in this scenario, most of these substances are not expected to cause adverse health effects. However, ground workers may be exposed to fluoride in amounts large enough to cause some adverse health effects should their exposure last for several years.
Ground workers are likely to be exposed to fluoride through the ingestion of contaminated soils and groundwater. If their exposure lasts for several years, the amount of fluoride that they are exposed to and the long-term, chronic nature of their exposure may produce adverse health effects. These effects may be overstated, however, since the aluminum that is also present at this site tends to decrease the amount of fluoride absorbed into the bloodstream. Although low levels of fluoride can be beneficial by reducing the incidence of dental cavities, high levels of fluoride can cause the opposite effect--an increase in dental cavities. The bones also absorb fluoride. When such absorption occurs at high levels for several years, it can result in decreased amounts of calcium in the bone and a thickening and weakening of the bones. This combination causes an increased risk for bone fractures. In more severe cases, the spine may become involved, resulting in either a humped or an arched back [ATSDR, 1993a].
B. HEALTH OUTCOME DATA
This section contains an evaluation of available information regarding the health of people in the surrounding area. This information is focused only on those adverse health effects that may result from people's exposure to contamination at this site. Health outcome data is evaluated to determine whether there is evidence that people have experienced adverse health effects that are identified as being possible through exposure to site contamination.
Skeletal fluorosis in ground workers at the Reynolds site is the only adverse health effect identified as being possible. Because Reynolds Metals has employed as many as 950 people in the past, many people in the area may have the potential for developing some signs of the absorption of fluoride into their bones and teeth. Unfortunately, there is no registry of persons who may have skeletal or dental fluorosis. Therefore, it is not possible to evaluate whether the fluoride contamination at this site has resulted in an increased incidence of this condition.
C. COMMUNITY HEALTH CONCERNS
Community members have not voiced health concerns regarding this site. ATSDR staff members have met with representatives from the City of Troutdale, the Oregon Division of Health, and the EPA; none of these organizations had found any community interest in the site. ATSDR also placed a public notice in the Gresham Outlook, a local biweekly newspaper, requesting information from concerned citizens. There have been no replies.
Workers at the site have voiced concern about on-site PCB contamination. Because this issue surfaced
only recently, ATSDR will address it in a document separate from this public health assessment.