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BioNebraska, Inc.-BiMelyze Field Screening Assay

Final Decision to Certify Hazardous Waste Environmental Technologies

Published Weekly by the Office of Administrative Law
Register 95, No. 29-Z
July 21, 1995
pp 1167-1170

The California Environmental Protection Agency, Department of Toxic Substances Control (DTSC) intends to certify the following company’s hazardous waste environmental technology listed below:


BioNebraska, Inc.
Lincoln, Nebraska 68524

BiMelyze® Field Screening Assay for Mercury
(“Tube Assay”) and Soil Extraction Kit.

Chapter 412, Statutes of 1994, Section 25200.1.5, Health and Safety Code, enacted by Assembly Bill 2060, Weggeland 1993, authorizes DTSC to certify the performance of hazardous waste environmental technologies. Only technologies that are determined not to pose a significant potential hazard to the public health and safety or to the environment when used under specified operating conditions and which can be operated without specialized training and with minimal maintenance may be certified. Incineration technologies are explicitly excluded from the certification program.

The purpose of the certification program is to provide an in-depth, independent review of technologies at the manufacturer’s level to facilitate regulatory and end-user acceptance and to promote and foster growth of California’s environmental technology industry.

DTSC makes no express or implied warranties as to the performance of the manufacturer’s product or equipment. The end-user is solely responsible for complying with the applicable federal, state, and local regulatory requirements. Certification does not limit DTSC’s authority to require additional measures for protection of the public health and the environment.

By accepting certification, the manufacturer assumes, for the duration of certification, responsibility for maintaining the quality of the manufactured equipment and materials at a level equal or better than was provided to obtain certification and agrees to be subject to quality monitoring DTSC as required by the statute under which certification is granted.

DTSC’s notice of intent to certify was published on June 2, 1995, in the California Regulatory Notice Register Volume 95, No. 22-Z, p. 873-876. Written comments in relation to the proposed certifications received during the public review and comment period have been duly considered in the final certification as presented here. DTSC’s final certification shall become effective on Monday, August 21, 1995.

Additional information supporting the DTSC’s final certification decision is available for review at:

California Environmental Protection Agency
Department of Toxic Substances Control
Office of Pollution Prevention and Technology Development
P.O. Box 806
301 Capitol Mall, 1st Floor
Sacramento, California 95812-0806
(916) 322-3670

A description of the technology to be certified, the final certification statement and the certification limitations for the technology of each of the company listed above follows.




BiMelyze® Field Screening Assay for Mercury
(“Tube Assay”) and Soil Extraction Kit


BioNebraska, Inc.
Lincoln, Nebraska 68524

Certification Statement and Technology Specifications

Under the authority of Section 25200.1.5 of the California Health and Safety Code, DTSC hereby certifies the BiMelyze® Field Screening Assay for Mercury (“Tube Assay”) and Soil Extraction Kit, manufactured by BioNebraska, Inc., Lincoln, Nebraska 68524 as a Measurement Technology.

The BiMelyze Field Screening Assay (“Tube Assay”) test kit provides the user with a semiquantitative immunoassay system for the detection of mercury in water and a Soil Extraction Kit which is used together with strong acid reagents, which the user provides, for the conversion of other forms of mercury into mercuric ion and subsequent processing by the Tube Assay. mercuric ion is the chemical form of mercury detected by the immunoassay. Of the inorganic and organic forms of mercury tested, only methyl mercury requires an extended extraction step for detection by the assay, provided the assay is used properly, detection of mercury is possible in a range from 0.25 to 25 ppb in water, 0.5 to 50 ppm in soil. Actual use is for classification of samples above and below the target levels of the actual target levels of the testing kit provided by the manufacturer, typically 5 and 15 ppm for soil; for water, a 100 ppm Hg standard is provided, which is diluted by the user into the target range that is appropriate for the study. Readings about these target levels are obtained by comparing sample and standard either visually or in a battery-powered differential photometer supplied by the manufacturer. For field studies in a higher concentration range, the user should rely on the manufacturer to provide a customized assay kit for the range or use the manufacturer’s dilution buffer, as appropriate, DTSC’s findings are described in greater detail in an evaluation report.

Limitations of Certification

DTSC makes no express or implied warranties as to the performance of the manufacturer’s product or equipment. DTSC has not conducted bench or field tests to confirm the manufacturer’s performance data. Nor does DTSC warrant that the manufacturer’s product or equipment is free from any defects in workmanship or material caused by negligence, misuse, accident, or other causes.

DTSC believes, however, that the manufacturer’s product or equipment can achieve performance levels set out in this Certification. Said belief is based on a review of the data submitted by the manufacturer and other information, and is based on the use of the product in accordance with the manufacturer’s specifications.

Specific Conditions

1. Manufacturer states that BioNebraska will continue to provide training sessions to the operators if requested by the customer. The manufacturer shall include this statement in testing protocols for the user.

2. Manufacturer shall express stability by displaying an expiration date on the package which is based on the date of manufacture and consistent with the results of ongoing studies on reagent stability.

3. Manufacturer shall include in instruction leaflets the possible effect of gold preservation of samples on the BiMelyze Mercury Tube Assay.

4. Manufacturer shall inform the users of the useful temperature range for the assay.

5. Manufacturer shall stay abreast of results of ongoing field validation studies, new findings on matrix effects, possible sources of interference, and other relevant facts, and issue revised user advisories as appropriate.

Basis for Certification

The documents submitted by the manufacturer are listed in the evaluation report. The manufacturer has declared that certain submitted materials contain proprietary information and should not be subject to public disclosure.

Recommended Applications

The immunoassay was developed for, and indicates, mercuric ion. Through conversion of other forms of mercury into mercuric ion using pretreatment with strong acids and oxidants, the assay is suitable for the semiquantitative determination of total mercury. A distinction among forms of mercury would be possible to some extent by measuring the difference in mercury content in samples that are pretreated and others that are not. There is no correlation, however, between the toxicity of forms of mercury and the treatment needed to transform them into mercuric ion. A semiquantitative determination will provide a response, interpreted as either positive or negative, at one or several predetermined detection or target levels. Target levels are usually chosen to have relevance to a specific situation (such as a regulatory limit or cleanup level).

A comprehensive process of developing data quality objectives (DQO) was published by U.S. EPA under the U.S. Superfund Program. It provides guidance for analytical method QA/QC as applied to field investigations for contaminated soils. The process is intended for site-specific sampling plans. The immunoassay would generally qualify as a Level 2 (field analysis) method, subject to confirmation by a Level 3 method (identification and quantification, i.e., EPA Methods 7470 or 7471) applied predominantly to positive results. DTSC recommends that minimum quality control should include method blanks and duplicates at 5 percent, or one per batch or per matrix, whichever is the more frequent, in addition to the samples required for confirmation. The use of proficiency evaluation and spiked samples should depend on project-specific needs.

We recommend U.S. EPA Methods (cold vapor atomic absorption) for establishing or confirming the concentrations of total mercury, i.e., SW-846 Methods 7470 and 7471 for solid waste, and 245.1, 245.2, or 245.5 for water wastewater, and sediments.

Screening and Preliminary Site Investigations

The immunoassay can assist in preliminary site investigations, if there are compelling historical data to indicate the presence of mercuric compounds. If used on samples of largely unknown composition, confirmatory analysis is needed for every positive immunoassay result. Users should note the requirement for extended digestion to convert methyl mercury into a chemical form detected by the assay. No negative determinations can be made without taking into account the specificity of the assay and its possible susceptibility to interferences and matrix effects.

In the absence of other regulations and guidelines, DTSC recommends that assay results be confirmed in the following manner:

(a) For the delineation of mercury contamination in a coherent mass of soil, the required frequency of confirmation by an approved method resulting in identification and quantification is at least 10 percent of the samples testing positive at the target or action level applicable at the site. In the event that fewer than ten samples meet these criteria, at least one positive sample shall be confirmed. Higher rates of confirmation apply if there is a potential for chemical interferences.

(b) Ten to twenty percent of results which are above the detection level, but below the target or action level should be confirmed by an approved, fully quantitative method, except that a higher rate of confirmation and speciation of the mercury may be necessary, if the results are to be used in health risk assessments.

(c) Five to ten percent of all negative results, but no less than one result from each site or suspect area, should be confirmed..

If appropriate protocols are followed, the immunoassay can be used to advantage to classify contaminated soils as to low, medium, or high contamination and to determine which samples would provide the most information from laboratory analysis.

Site Investigations and Remedial Actions

This testing is expected to proceed under a site-specific Quality Assurance Project Plan (QAPP). Immunoassay and other field measurements will be “bracketed” in time and space by qualitative and fully quantitative analyses. Generally, a site is first characterized by the use of approved, fully quantitative analytical methods az to the nature and level of contamination in key sampling locations and as to the presence of substances that may interfere with the use of the immunoassay. After such initial characterization, the immunoassay can be used in the comprehensive mapping of the site with respect to identified contaminant(s) to which the immunoassay responds. The percentage of samples that would be confirmed by another approved, fully quantitative method would be as stipulated in the QAPP; the project manager could call for additional confirmatory testing if such a need is indicated in the course of the investigation. During site cleanup, the QAPP would provide for use of the immunoassay to monitor progress. Confirmatory laboratory testing would occur before a decision on site closure is made.

Environmental and Economic Benefits

If the immunoassay system is used as recommended in this report, it offers a distinct advantage in environmental management and control by increasing the amount of reliable data available in the characterization and remediation of hazardous waste sites containing mercury, at significantly reduced turn-around time and at a cost below the cost of providing these date with presently available, approved laboratory methodology alone. Provided that reagents and other materials are properly disposed of, the use of the assay does not introduce new or additional public health or environmental hazards.

Regulatory Implications

DTSC’s Certification is based on the technology’s performance and by itself does not change the regulatory status of mercury testing; it should, however, facilitate and encourage the acceptance of this technology where a project’s data quality objectives can be met by its use. To this end, DTSC’s findings should contribute to a consideration of this technology in regulated activities, depending on each regulated program’s objectives and constraints.

State certification does not imply certification by the U.S. Government for use at federal superfund sites and other facilities under the jurisdiction of the U.S. Government for which state authorization for administrative oversight has not been granted. Under state implementation of the U.S. Resource Conversation and Recovery Act (RCRA), Treatment, Storage, and Disposal Facilities may contact state permitting agencies for use of the immunoassay for operational monitoring as part of a waste analysis plan.

This Certification is issued as part of a pilot project to expedite the California Environmental Technology Certification Program. As a result, this Certification is subject to the conditions set out in the regulations to be developed, such as the duration of the Certification, the continued monitoring and the oversight requirements, and the procedures for the certification amendments, including decertification.

By accepting this Certification, the manufacturer assumes, for the duration of the Certification, responsibility for maintaining the quality of the manufactured materials and equipment at a level equal or better than was provided to obtain this Certification and agrees to be subject to quality monitoring by DTSC as required by the law under which this Certification is granted.

For more information, contact us at:

Department of Toxic Substances Control
Office of Pollution Prevention and Technology Development
P.O. Box 806
Sacramento, California 95812-0806
Phone: (916) 322-3670
Fax: (916) 327-4494

File last updated: October 9, 1996