Dioxin Study



A Review of Dioxin Accumulation Studies - Health & Water Quality Issues in the Angelina River

 Walter West, P.E.

 Summary / Introduction  - Studies to determine the concentration of toxic Dioxins in fish tissue of specimens collected in the Angelina River and other water bodies down stream of paper mill plants and the associated human health risks are reviewed herein.  It is concluded that the studies are inadequate to assess human health risk from consumption of fish. 

The review also disclosed information relevant to the proposed standards revision for the upper reaches of Sam Rayburn Reservoir.  Based on water chemistry and fish species information disclosed in this review a High Aquatic Life Designated Use Standard is appropriate for the Angelina River – upper reaches of Sam Rayburn reservoir. The Intermediate Aquatic Life Standard being proposed to the Texas Natural Resources Conservation Commissioners is not supported and the privately funded site-specific study ostensibly justifying the proposed revision to standards is contradicted. 

Recommendations pertinent to human health issues and the recreational value of Sam Rayburn reservoir are made for the consideration of the Texas Political Body, the Texas Natural Resources Conservation Commission, The Texas Department of Health, and the U.S. EPA are made.

Dioxins / Sources  - Dioxins are unwanted highly toxic byproducts of paper mill processes that use chlorine bleaching agents and are also produced by incineration of industrial wastes.  Dioxins have an affinity for fatty tissue and they accumulate in animal and fish tissue to the extent they create significant health risks for consumers of fin fish, crabs and oysters. 

Prior Assessments / Studies - The U. S. EPA conducted a nationwide assessment identified as the National Bioaccumulation study  (NBS) in 1986-1987 to determine if significant biological accumulation of Dioxins was occurring in fish tissue. As a follow up to the National study, Region 6 of the EPA collected additional fish specimens from 9 sites located in Texas, Louisiana, and Arkansas to “resolve uncertainty” about human health risks in 1989.  Eight of the 9 sites selected for study were located downstream of paper mill discharges because paper mills using Chlorine bleaching agents are a principal source of Dioxins.

Dioxins and contaminants such as Mercury accumulate in the upper end of the food chain and predator fish tissue.  Based on these early EPA assessments, it is apparent that the species and size and age of the fish specimens is an important  factor.  Obviously, greater biological accumulations should be expected in older adult specimens than in juvenile specimens.  Although the follow up EPA study recommended collection of one catfish species, one bass species and one sunfish or crappie species, the actual species collected  in their study were predominantly trash fish; i.e., gar, buffalo, drum, mullet.  In the Houston ship channel area blue crabs and oysters were also collected

According to the 1990 EPA report of the follow on study, only under size crappies (7.0 & 9.4inches), drum (13 & 14 inches) and blue gill were collected and assessed on Rayburn below Paper Mill Creek.   Toxic accumulations in these fish tissues were very small. In the NBS survey of 1987 only white bass were collected downstream of Paper Mill Creek.  The white bass had a Toxic concentration value (TEC) of 1.08 ppt. Correspondence from the EPA report author also indicates that catfish having a TEC value of 3.16 ppt were found although this specimen was not filleted and the whole fish was analyzed.  The 3.16 value would warrant a fish consumption advisory in Louisiana.

Human Health Risk Assessment - An EPA document[1] published March 1990 presents results of the study which supplemented the 1986 – 1987 National Biological Accumulation Study of Dioxins in fish tissue.   The supplemental study took place in EPA Region 6 and included analysis of fish tissue collected in streams downstream of Paper Mills which use Chlorine bleaching agents in Arkansas, Louisiana, and Texas.  In this study, the EPA recommends that states issue a fish consumption advisory when concentrations of Dioxins in fish tissue reached levels of 7.0 ppt (parts per trillion).  In Louisiana, the state issues health advisories when Dioxin concentrations in fish tissue exceed 2.3 ppt, according to the EPA document published in 1990.  The more conservative risk assessment in Louisiana is due to an assumption of fish consumption per day of  20 grams whereas the EPA made their recommendation assuming a 6.5 gram per day consumption rate.  The following table illustrates the human cancer risk assessment relationship with quantity consumed and Dioxin concentration in fish tissue.  The importance of consumption rate in assessing cancer risk caused by eating fish contaminated with Dioxins is also illustrated by this table. 





Risk Assessment




Lbs. per year

Lbs. per month

TEQ in Tissue


Lbs. per year

Lbs. per month

TEQ in Tissue















·        Dioxin TEQ concentration in fish tissue (parts per trillion) that corresponds to the risk value entered in the left hand column of the table. The EPA recommends issuing health advisories at risk level equals to or greater than 1/10,000.  Louisiana also issues health advisories at risk levels of 1/10,000. 

Other assumptions common to both EPA and Louisiana State risk assessments follow.  Risk assessment as presented above is based on an assumed body weight of 154 lbs. and a life expectancy of seventy years. Small people will be at greater risk than large people if both consume the same quantity of contaminated fish. One other very important assumption is made in the above approach to risk assessment.   The risk assessments ignore the fact that significant levels of Dioxins are normally accumulated in the body from sources other than fish. We do not start consuming fish with a zero accumulation of Dioxins. In fact, Dioxins are now found in human breast milk.  Since Dioxins accumulate, the total from all sources will be greater than just that attributable to fish consumption.  The preceding risk assessment summary is based on the available information published in 1990. The EPA recently released information announcing that they now conclude that Dioxins are carcinogenic to humans and Dioxin is longer identified as a suspected human carcinogen.  The new EPA assessment reports that the risk of getting cancer from Dioxin contamination is 10 times greater than that estimated in 1994. 

Conversation with Texas Department of Health (TDH) Representatives on April 25, 2000 disclosed several important issues. 

1)      Texas does not have a fixed policy, law, rule or guide line for determination of the specific concentration of Dioxins that would result in issue of a health advisory for consumption of fish tissue even though health advisories have been issued. The Texas Department of Health has issued advisories for the Houston ship channel and San Jacinto River areas down stream of two paper mill plants which are located at Sheldon (Donohue plant) & the Washburn Tunnel. These advisories recommend limited consumption of finfish, shell fish and crabs because of large concentrations of Dioxins. 

2)      Even though the Texas Department of Health (TDH) has issued health advisories through media, they do not post signs warning the public of the health risks associated with consumption of fish, and crabs containing dangerous concentrations of toxic substances. The TDH has several health advisories in effect in the state, including an advisory recommending limited consumption of Sam Rayburn, Toledo Bend and other East Texas fish because of excessive Mercury concentrations.

Recent Dioxin Studies –

Recently it was discovered that Champion / Donohue paper manufacturers reported analyses of fish tissue collected downstream of Paper Mill Creek for 1994 through 1997 and 1999 to TNRCC.  No report of analysis of fish tissue for the year 1998 was provided by TNRCC in response to an initial request for data.  The data table provided initially did not describe fish sizes that were reported as being examined in the Champion / Donohue funded studies.

Since the information initially available for the assessment of fish tissue from the fish species downstream of Paper Mill Creek was incomplete and not adequate to evaluate risk associated with Dioxin concentrations typically found in fish populations downstream of paper mill plants a formal request was addressed to TNRCC in late April asking for the 1998 data and study details, including definition of fish size, analysis lab identification, etc. The 1998 data was of particular interest because of the fish kill episode that occurred on Rayburn in the summer of 1998.

Dioxin Assessment in Angela River – Sam Rayburn tributary  - In response to the formal request, TNRCC provided reports of the results of analyses for Dioxin concentrations in fish collected in the Angelina River above and below Paper Mill Creek, which receives the waste water discharged by the local paper mill.  These reports[2] document the results of the Champion / Donohue paper mill funded collection and analyses of fish tissue in specimens collected at three locations in the Angelina River.  Two locations were above the confluence of Paper Mill Creek with the Angelina River and one location was below. Reports were received from TNRCC on June 9, 2000.  The reports cover a period from 1994 through 1999.

Permit 00368 Dioxin Assessment Plan Terms  - The following is excerpted from the EA Engineering, Science, and Technology (EA) reports2.  Under the terms of the permit, three species of fish with a minimum of five adult fish per species should be collected from all sites.  The target species for tissue analysis are listed in the permit and include common carp, white sucker, channel catfish, flathead catfish, and blue catfish as bottom feeding fish.”  The plan allows collection of shellfish (clams and crawfish) as alternatives to bottom-feeding fish.  “Recommended predators are the white bass, smallmouth bass, largemouth bass, crappie, and bluegill.”

The species selection section of the plan appearing in all the EA reports proposes “that smallmouth buffalo and freshwater drum be considered acceptable alternate species for this study along with bull heads”. 

The following table lists the target species and size appearing in the plan appended to the reports.


SIZE - inches

Largemouth Bass




Bluegill Lepomis species



SIZE - inches

Common carp


Smallmouth Buffalo




Channel catfish


Blue catfish


Flathead catfish


Note that current game fish regulations prohibit taking crappie smaller than 10 inches. 

Collection Techniques – The fish collection section of the plan states “EA’s field crew will be equipped with an array of fishery gear which will enable collection under a variety of conditions”.  It also says; “successful collection of catfish may require trotlines and netting as well”.  Also; “every effort will be made to collect desired species and numbers of fish”. The plan required detailed notes at each site defining environmental parameters including routine water chemistry  (e.g., pH and dissolved oxygen), temperature, and conductivity. Specimens were to be examined for anomalies and recorded on a fisheries data sheet as well.  The reports also include appendices identified as Laboratory Data sheets and Field Notes.   

Consideration of the Results section herein will establish that the actual work performed and reported by EA deviated from the plan. It is obvious that the plan was not regarded as much more than a vague outline of a task to be performed.

Specimen Collection & Laboratory AnalysisEA, Engineering, Science and Technology, Inc, Carrolton, Texas collected all the fish specimens that were analyzed and prepared the reports documenting the analysis results. Laboratory analysis to detect Dioxins was performed by three different laboratories. In 1994 and 1995, a Champion International owned laboratory performed the analysis for Dioxin content and in 1996 Quanterra Environmental Services, Cal. performed the laboratory analysis.  In1997 the Champion owned lab again performed the analysis and in 1998 and 1999 Alta Analytical Laboratory, California, did the lab work.

In 1994, electro-fishing, gill nets, and slat traps were used to collect specimens.  The slat traps and gill nets were fished continuously at site 2 for 16 hours and for 45 hours at site 3 which is below Paper Mill Creek.  The disparity in time required to collect the required samples may indicate significant differences between fish populations above an below Paper Mill Creek.   The reports for all other years (1995 – 1999) indicates that electro-fishing was the only method employed.  This may explain the relatively large specimen sizes collected in 1994.  The use of electro-fishing methods alone subsequent to the 1994 collection, does not comply with the permitted plan to use “every effort to collect desired species and numbers of fish”.

The analysis plan required the collection of five specimens each, from three species at each of three sites or areas of the Angelina river. The reports claim that the fish collection location was relevant to the Dioxin source, and collection of Dioxins in fish collected below the Creek were associated with the paper mill discharges. Unidentified sources other than the paper mill were claimed to be the contributors  to Dioxin concentrations found in fish collected above Paper Mill Creek in these reports. This hypothesis is not credible because fish are mobile as proven in prior EPA investigations.     

Two areas or collection sites were above Paper Mill Creek and one was below.  This doubles the total sample size collected above Paper Mill Creek relative to the sample size below Paper Mill Creek.  All other factors being the same, one would expect that twice the number of contaminated fish would be found above Paper Mill Creek because the total sample size (numbers of fish) collected above the Creek was twice that collected below. The EPA report1 documents a large mouth bass contaminated with Dioxin collected 65miles away from the nearest Dioxin source and a sheephead 50 miles downstream from the nearest known source. There are no gates or any devices limiting fish ability to travel in the Angelina river and fish may move upstream and downstream, a fact documented in the prior EPA report.

The requisite five specimens were filleted by EA personnel and shipped to the analysis lab. Laboratory personnel then prepared a composite sample from the five (large and small) specimens for each of three species. The resulting composites were then analyzed to determine the Dioxin concentration in the fish tissue of each species.   Similar procedures were followed for all species collected at all three locations for each of the six years reported.

Results  - The results of the fish collection and laboratory analysis are presented in Tables 1 and 2.  The tables also present a synopsis of the limited field notes that were reported. Several conclusions that can be drawn from study of these tables follow:

1.      Dioxins are accumulating in fish in the Angelina River.

2.      Dioxin concentrations are significantly greater in larger fish than in smaller fish.  In 1994, one species (Buffalo) had a Dioxin concentration value of 7.018.  Note that this is the only year that methods other than electro-fishing were employed to collect fish even though the plan specified that “every effort will be made to collect the target species listed in the permit”.

3.      Dioxins were detected in fish tissue both above and below the confluence of Paper Mill Creek and the Angelina River.

4.      The 1998 analysis was unique in that it was the only year in which all species examined had detectable levels of Dioxin.  This is also the year that a major fish kill episode occurred on Sam Rayburn.

5.      Many of the fish collected and analyzed were smaller in size than that specified by the permitted plan. For example, three of the five Channel catfish collected were below the specified minimum size of 12 inches in 1998. 

6.      The size and species collected year to year and site-to-site were varied and inconsistent. 

7.      The field notes appended to the reports are incomplete and do not comply with the plan.

8.      The few available field notes indicate that the dissolved oxygen (DO) values down stream of Paper Mill Creek were always less than 4.0 mg/liter and were consistently greater then 5.0 mg/liter above Paper Mill Creek.  Values greater than 3.0 were only measured at the surface below Paper Mill Creek and the DO values were usually less than 3.0 below Paper Mill Creek.  Values of DO 4.0 and below are intrinsic to the TNRCC Designated Use Standards of Intermediate Aquatic life and DO values of 5.0 and greater are intrinsic to the TNRCC High Aquatic Life Designated Use Standard.

9.      Field notes in the 1999 report indicate that the water conductivity was abnormally high downstream of Paper Mill creek.  Attempts to operate the Electro-fishing apparatus in the mainstream downstream of Paper Mill Creek resulted in “blown fuses”.  No such problems were reported at any other time or location. The high conductivity can be associated with the Acute concentration of dissolved Aluminum in Rayburn documented by TNRCC water quality data as reflected in the Impaired Waters List, 303d, 2000.  It is logical to attribute the condition to the Donohue Paper Mill discharges of Aluminum greater than 200,000 lbs. / year into the Angelina River evident in the self reported effluent discharge records available from TNRCC.  

10.  Field notes in the 1999 report indicate that many of the fish collected had lesions.  These lesions were detected on fish specimens collected in August, 1999.  Biologists often attribute the presence of lesions to a protozoan called Epistylus and claim that it usually occurs during periods of temperature change (e.g.., spring and fall) and it is usually associated with poor water quality.  Perhaps the outbreak of lesions that plagued many of the Rayburn fish was due to causes other than Epistylus. 

Conclusions – The basis for the information presented herein was taken directly from documents available from the EPA and TNRCC.

Dioxins are accumulating in the fish population of the Angelina River and it is likely that Dioxin accumulations are occurring in the Sam Rayburn fish population as well.  Sam Rayburn reservoir water chemistry analyses performed for the City of Lufkin to evaluate the reservoir use as a drinking water source detected Dioxin at small concentration levels.

In these studies only one fish collection (Buffalo) was shown to have a Dioxin concentration sufficient to warrant a health advisory per EPA recommendations as defined in 1990.  The concentrations detected in Gar fish populations are at marginal levels for Louisiana health advisories as defined in 1990. The recent EPA announcement of increases in the estimated toxicity of Dioxins should be cause for concern. An obvious dependency between fish size and Dioxin concentration is made evident in these studies.  The lack of truly adult fish collected in these studies and the failure to follow the permitted plan and collect popular catfish species and adult sizes prevents rigorous conclusions pertaining to human health risk associated with consumption of Angelina River and Sam Rayburn fish.

Dioxins are no longer identified as a suspected human carcinogen.  The EPA recently released information announcing that Dioxins are carcinogenic to humans. The new EPA assessment states that the risk of getting cancer from Dioxin contamination is 10 times greater than estimated in 1994.

The unique uniformity of Dioxin detects in all collected species in 1998 and the inability to operate the electro-fishing apparatus downstream Paper Mill Creek because of excessive conductance which resulted in “blown fuses” reported in the field notes are indicative of abnormal water chemistry conditions.  Certainly the remarkable conductance values reported in 1999, downstream of Paper Mill Creek are abnormal relative to other geographic locations and normal water chemistry conditions. The proximity to the paper mill and their Aluminum discharges is very likely the cause. 

 The timing of; 1) the major fish kill episode occurring on Sam Rayburn in 1998, 2) a minor fish kill in 1999, 3) an increased incidence of fish with extensive lesions,  4) the unique uniformity of Dioxin detects in 1998, and 5) the preceding purchase of the Paper Mill by Donohue, if actually unrelated coincidence, must be considered remarkable.  Some would say that to conclude or claim there is no association between this string of coincidences may be a self serving conclusion, that would not be verified in a rigorous scientific investigation free of political influence.

The fundamental premise of the privately funded site-specific study submitted by Champion / Donohue to TNRCC which claims that the upper reaches of Sam Rayburn (newly designated segment 615) should have a Designated Use Standard of Intermediate Aquatic Life is contradicted by these reports. The available field notes indicate that the dissolved oxygen (DO) values down stream of Paper Mill Creek were always less than 4.0 mg/liter and consistently greater then 5.0 mg/liter above Paper Mill Creek. DO values greater than 3.0 were only measured at the surface below Paper Mill Creek and  values were usually less than 3.0 below Paper Mill Creek.  Values equal to or less than 4.0 mg/liter are intrinsic to the TNRCC Designated Use Standards of Intermediate Aquatic life and DO values of 5.0 and greater are intrinsic to TNRCC High Aquatic Life Designated Use Standards.  The disparity in measured DO values above and below Paper Mill Creek proves conclusively that the effluent discharged into Paper Mill Creek is detrimental to Aquatic life and nullifies the argument that the rivers ability to support aquatic life would be the same if the Paper Mill were not present.  The fact that game fish representative of High Aquatic Life were collected at all sites also contradicts the site-specific study.

 Down grading the upper reaches of Sam Rayburn based on the privately funded site- specific study claims that the Angelina river natural state is only supportive of Intermediate Aquatic life is a sham and a mockery of scientific reasoning.  The proposed revision provides a vivid demonstration that TNRCC is protecting industrial interests - not public interests.  This statement is made with cognizance of economic considerations and awareness that closed loop paper mills are being successfully operated with practically no discharge of effluents into surface or ground waters.

The Texas Department of Health (TDH) has no policy, rules or guide-lines to consider in the decision process culminating in Human Health Advisories.  The (TDH) failure to post warning signs advising the public of existing health advisories is irresponsible when the cancer incidence rate is considered.  The public is warned by posted signs such as; Do Not Litter, Buckle Seat Belts, Drive Safely, Watch for Under Water Hazards, etc, etc., but there are no posted signs at popular fishing sites warning the public of the risks associated with consuming contaminated fin and shell fish in areas under health advisories because of  fish tissue contamination such as Mercury and Dioxins. One can only speculate as to the reasons warning signs are not posted. TDH officials claim that a lack of funding and removal and destruction of posted signs when posted are the reasons for not posting warnings. Are signs posted along Texas high ways ever damaged or destroyed by gun fire?  A plausible explanation for the lack of posted warnings is a reluctance to bring the publics attention to water pollution issues.  It would be interesting to determine the actual funding spent posting Health Hazard signs in Texas.

Recommendations – TNRCC should consider the reported dissolved oxygen values above and below Paper Mill Creek.  The values contradict the fundamental premise of the proposed standard revision premise that the natural condition of the Angelina River will not support a High Aquatic Life Designated Use Standard, as alleged by the privately funded site specific study submitted by Champion / Donohue paper mill owners.  The privately funded study does not justify the proposed revision to Intermediate Aquatic life being submitted to TNRCC commissioners for approval. 

 TNRCC should consider the species of fish and the location where they were caught documented in these reports.  The species collected represent High Aquatic Life species and the fact that they were caught in the river contradicts fundamental premise that the river will only support a designated Use Standard of Intermediate Aquatic life.

Should TNRCC choose to pursue the first two recommendations they should make public the rationale that explains the disparity in dissolved oxygen in waters above and below Paper Mill Creek and attribute the disparity to causes other than the Paper Mill effluent.  Doing so might salvage agency creditability

TNRCC should become aware of and familiar with the paper mill operations currently running successful closed loop operations without significant discharges into surface or ground waters and consider if they can legitimately justify the proposed standard for the newly designated Segment 615 on economic grounds.

TNRCC should not submit the proposed revision to Designated Use Standards for the upper reaches of Sam Rayburn reservoir (segment 615) based on the pseudo science offered in the privately funded studies.   

TNRCC should become familiar with and evaluate the water chemistry reports prepared for the City of Lufkin as part of their drinking water feasibility study

More assessments for Dioxin concentration in fish populating the Angelina River should be conducted.  Future assessments should emphasize collection of adult target species that are popular for human consumption such as Channel, Blue and Flathead catfish. Complete field notes documenting water chemistry and other observations, as specified in the 00368 permitted plan, should be made and included in the reports.  Methods of fish collection other than electro-fishing should be used to ensure collection of fish that are representative of those normally consumed with none less than legal size.  In future assessments the electro-fishing apparatus should be adjusted and utilized effectively to collect popular non-scale catfish e.g., Blue, Channel and flathead species as specified by the original TNRCC approved plan, not just scale fish.  

The TDH should post warning signs in popular fishing locations that are under advisories to limit fish consumption because of contaminants. 

The TDH and TNRCC should plan and perform a study that considers the multiple source intake of Dioxins in the populace. Any Dioxin risk assessment of value must account for the Dioxins normally accumulated from all sources not just fish consumption.


[2] FINAL DIOXIN MONITORING IN FISH TISSUE 1994, 1995, 1996, 1997, 1998, 1999 Report,  Prepared by EA Engineering, Science, and Technology, Inc. Carrolton, Texas (six reports)




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