MAINE HEALTH AND ENVIRONMENTAL TESTING LABORATORY



About This Document

The section supervisor and appropriate staff members review the procedures contained in this document annually. Any changes are also reviewed by the Quality Assurance Officer and the designated ASCLD-LAB Director. All Changes are signed. Old procedures are archived and retained in the laboratory for at least two years.

TABLE OF CONTENTS

I. Evidence Handling and Preservation

A. Evidence Control

1. Chain of Custody

2. Evidence Log-In StarLims Procedure

B. Evidence Handling and Packaging

1. Proper Handling

2. Packaging

II. Quality Control

A. Equipment Maintenance and Calibration

B. Reagents, Standards, and Quality Control Materials

C. Quality Control

D. Criteria for Evaluating Blanks in GC/MS Analysis

E. POLICY FOR REPORTING UNCERTAINTY OF MEASUREMeNTS

General Case Handling Procedures

A. General Observations

1. Package Condition

2. IDENTIFICATION NUMBERS

3. Evidence Description

4. Sealed Package Weight

5. Gross Weight

F. Analysis

1. Net Weight

2. Evidence Sampling Plan

G. Identification Requirements

1. Minimal Requirements for Complete Identification

2. Minimal Requirements for Preliminary Identification

III. Case Documentation

A. Case Notes

B. Case File

IV. General Analytical Procedures and Criteria for Evaluating Unknowns

A. Color Tests

B. Thin Layer Chromatography

C. Gas Chromatography/Mass Spectrometry

D. Fourier Transform Infrared Spectroscopy

E. High Performance Liquid Chromatography

V. Specific Analytical Procedures

A. Marijuana/Hashish

B. General Powders/Residues

C. Quantitation of Powder Samples

D. Tablets/Capsules

E. Suspected LSD

F. Psilocybe Mushrooms and Food Products

G. Liquid Samples

I. Evidence Handling and Preservation

A. EVIDENCE CONTROL

1. Chain-Of-Custody

AT THE TIME OF RECEIPT, EACH CASE WILL RECEIVE A LABORATORY IDENTIFICATION NUMBER. WHENEVER POSSIBLE, ALL PERTINENT INFORMATION CONTAINED ON THE RECEIPT/CONTRACT FOR EXAMINATION FORM WILL BE COMPLETED WITH EVERY SUBMISSION TO THE HETL FORENSIC CHEMISTRY SECTION (FCS). THE RECEIPT WILL BE COMPLETED IN TRIPLICATE AND THE COPIES DISTRIBUTED AS FOLLOWS:

a. White copy (original) to submitter or case file

b. Yellow copy to case file

c. Pink copy placed in the appropriate file located in room 176.

The sealed package weight (SPW) will be taken and recorded on the evidence form. The sealed package weight (SPW) is the weight including the envelope, box, etc. containing the evidence

The recipient will mark all evidence and corresponding paperwork for identification with the laboratory number. The evidence will then be placed under locked condition in either the overnight storage safe, evidence refrigerator, evidence freezers, evidence cabinet (located in room 113), evidence safe or evidence room. Upon relinquishing control of evidence, transfers will be noted on the reverse side of the pink Receipt/Contract for Examination form. The back of the pink copy serves as the record of the internal chain of custody for the evidence.

When placing evidence into Evidence Storage, the reverse side of the pink copy will be completed and the form placed in the accountability file located in room 176. This copy must be annotated each time someone removes and returns evidence from/to evidence storage. All pink copies are maintained in the accountability file until such time as the evidence is returned or destroyed. This includes intra-laboratory transfers.

Evidence to be analyzed will be removed from evidence storage after completing the reverse side of the pink Receipt/Contract for Examination Form. The evidence will be brought directly into the laboratory for processing. A description of the item(s) and the condition of the packaging will be noted in the analyst’s case notes.

DO NOT CUT OR BREAK ORIGINAL SEALS, WHENEVER POSSIBLE, WHEN REMOVING ITEMS FOR ANALYSIS.

Chain-Of-Custody (continued)

During analysis the unsealed evidence will be under the control of the analyst. If the analyst must leave his/her work area for an extended period, all evidence will be placed in the analyst’s lockbox or evidence cabinet.

After analysis the evidence will be placed back into the original package, if possible, and sealed. The seal will be dated, signed or initialed by the analyst and the post sealed package weight (pspw) recorded on the container and in the case notes. Processed evidence will be placed into evidence storage until final disposition. At this time the information on the reverse side of the pink receipt form will be completed and retained in the appropriate accountability file.

Upon final disposition, the Receipt/Contract for Examination Form retained with the evidence will be removed from the accountability file and placed in the case folder.

B. Evidence Handling and Packaging

Preserving the integrity of evidence is crucial for proper interpretation and future admissibility at trial. Integrity of evidence is maintained through two practices:

1. Proper Handling

2. Proper Packaging

1. Proper Handling

ALL LABORATORY PERSONNEL WILL HANDLE SUBMITTED MATERIALS IN A MANNER THAT ASSURES THE INTEGRITY OF THE EVIDENCE. PRIOR TO INITIATING AND DURING THE PROCESSING OF EVIDENCE, THE ANALYST WILL EMPLOY THE FOLLOWING PRACTICES:

The work area will be clean and free of any debris –

2. Countertops are cleaned after each case/item or when dirty

3. Floors are swept frequently during the week

4. Garbage is removed daily

All glassware and tools to be used will be clean

Test tubes, capillary pipettes and Pasteur pipettes are used only once, then discarded

To prevent cross contamination of samples, only one case will be opened by the analyst at a time. Additionally, in cases involving multiple submissions, only one item will be opened by the analyst at a time of analysis.

All evidence will be stored under proper seal (see below)

Reagents and solvents will be kept in closed containers

2. Packaging

ALL EVIDENCE MUST BE PACKAGED IN A MANNER THAT ENSURES ITS INTEGRITY. THEREFORE, ALL EVIDENCE MUST BE RETAINED UNDER PROPER SEAL. PROPER SEAL IS DEFINED AS: CONTAINERS SEALED TO PREVENT THE LOSS OF CONTENTS AND SECURED IN A MANNER SUCH THAT ENTERING THE CONTAINER RESULTS IN OBVIOUS DAMAGE OR ALTERATIONS TO THE CONTAINER’S SEAL.

After the exhibit has been sampled for analysis, the exhibit will be re-packaged. The analyst will seal the container with evidence tape and sign their initials and date across the tape seal.

II. Quality Assurance

A. Equipment Maintenance and Calibration

Refer to Quality Assurance Manual

B. Reagents, Standards, and Quality Control Materials

Refer to Quality Assurance Manual

C. QUALITY CONTROL

Function checks will be performed to check the performance of equipment and regents used (either at regular intervals or while testing samples). Control checks will be performed during the analysis or testing process. These checks are used to:

• Determine the performance of the analytical or testing system.

• Quantitate (if possible) the variability of results from the analysis or test in terms of precision and accuracy.

The data from the check analyses will be compared with the expected values. Any significant difference (as determined by the analyst) shall be reported to the Section Supervisor.

For quantitation, control checks will be performed during the analytical or testing process. These checks are performed either with each analysis or intermittently after a specified number of analyses. These control checks include but are not limited to:

• Blanks

• Standard with known or established specifications.

• Controls

* Calibrators and standards shall be from different sources.

During the course of the analysis appropriate controls and standards are used to insure the validity of the analysis and that the procedure is working properly.

To determine the presence of a controlled substance and/or diluent on the GC/MS, the analyst will run and evaluate a blank containing the Internal Standard between each case sample. Evaluation of blanks is used to determine if a sample needs to be re-run or if there is a need for instrument maintenance.

D. Criteria for Evaluating Blanks in GC/MS Analysis

An acceptable blank will contain no target compounds as listed on the Quant QEdit Report for the method used and/or other compounds at the discretion of the analyst having a signal to noise ratio of greater than 3:1. In cases where the blank fails these criteria, the subsequent case sample vial will be re-run.

E. POLICY FOR REPORTING UNCERTAINTY OF MEASUREMeNTS

When estimating the uncertainty of measurement, all uncertainty components which are of importance shall be taken into account using appropriate testing procedures. The documentation containing the following information, if applicable, will be maintained in the Forensic Chemistry section:

a. What is being measured - Net weight of all suspected drug materials submitted to the Forensic Chemistry section of the HETL.

b. How traceability is established for the measurement - The traceability of weight measurements is established by using NIST traceable Class I weights or Ultraclass weights certified by an approved ISO 17025 accredited vendor.

c. The equipment used - The equipment used for measuring the net weights of suspected drug material are the following:

Analytical Balance: Sartorius Model: BP121S S/N: 90309414

Top Loading Balance: Fisher Scientific Model: ACCU 6201 S/N: 18208357

Floor Scale: Pelouze Model: 4010 S/N: DC3701

d. All uncertainty components considered - The factors considered when determining the accurate weight of the drug material contained within packaging is the amount lost due to mass transfer and the performance of the balances used to measure the weight.

e. All uncertainty components of significance and how they were evaluated - No analysis was performed to calculate random errors of loss due to mass transfer. Comprehensive balance checks are performed on a daily and weekly basis to ensure balances are performing within an acceptable tolerance range. An acceptable tolerance range is less than or equal to the off center load calculation from the external maintenance calibration report.

• Sartorius Model: BP121S S/N: 90309414 Off Center Load: +/- 0.0004 grams

• Fisher Scientific Model: ACCU 6201 S/N: 18208357 Off Center Load: +/-0.3 grams

• Floor Scale: Pelouze Model: 4010 S/N: DC3701 –

Tolerance:

0-100 pounds (+/- 0.2 pounds)

100-150 pounds (+/- 0.4 pounds)

f. Data used to estimate repeatability and/or reproducibility - Data from weekly and daily checks are input into a Microsoft Excel spreadsheet. (K:SDD UNCERTAINTY\chemistry balance statistics.xls)

g. All calculations performed - The average measurement, one standard deviation, two standard deviations, average plus and minus two standard deviations is calculated.

h. The combined standard uncertainty, the coverage, the coverage probability and the resulting uncertainty - Uncertainty is calculated using a coverage probability of 95.45%. Uncertainty of weight measurements (+/-) is reported using the external maintenance calibration report which has a greater allowable tolerance than the historical HETL balance statistics. Uncertainty is reported for all weight measurements.

i. The schedule review and/or recalculate the measurement uncertainty - Weekly and daily balance check data will be input into the existing spreadsheet and calculations updated on a monthly basis. If the tolerance of the balance exceeds the acceptable tolerance range, the balance will not be used until corrective maintenance can be performed and the tolerance of the balance returns to within the acceptable tolerance range defined above.

Single weights: the uncertainty will be estimated based upon the performance of the various balances used in the section. This can include manufacturer’s specifications, historical data on balance performance, and experiments conducted to estimate the uncertainty (standard deviation).

Multiple weights being added to meet a charge: this uncertainty would be based upon the uncertainty calculated for single weights. The standard deviation applicable to this addition of weights would be the square root of the number of weights multiplied by the standard deviation applicable to individual weights.

Weights estimated by weighing a sample of containers: for these cases the uncertainty would be calculated based upon the standard deviation of the weights of the empty containers, the value of “t” variables applicable to these weights, and the number of weights of the empty containers.

All the uncertainties calculated in the above cases will be based upon statistical techniques and will be calculated at or above two standard deviations.

For cases involving quantitative analysis: Maine Criminal Statutes (MRSA 17-A Chapter 45) do not contain regulations or penalties based on purity of controlled substances. Therefore, the HETL does not routinely perform quantitative analysis of solid dose drug samples. On occasion the HETL may be requested to obtain an estimate of percent purity of an analyte for investigative purposes. In such cases, accepted analytical quantitative practices will be employed. Results will be reported as “approximate %”

For cases involving sampling techniques:

The uncertainties in weight measurements in such cases will be based upon accepted statistical techniques (similar to the ones outlined above) and will be calculated at or above two standard deviations.

III. GENERAL CASE HANDLING PROCEDURES

GENERAL OBSERVATIONS

1. Package Condition

The analyst will note the condition of the evidence package: i.e.: Sealed or Unsealed.

2. Identification Numbers

The analyst will ensure all identification numbers agree with the chain of custody receipt (Receipt/Contract for Examination form).

The analyst will document the HETL case number and, if applicable, the submitting agency’s item number in the case notes.

3. Evidence Description

When applicable, the analyst will ensure evidence description(s) reasonably agree with the description provided by the submitting agency. If a discrepancy exists between evidence descriptions no testing will be conducted until reconciliation between the analyst and the submitter (or their representative) is accomplished. (NOTE: refer to Quality Assurance Manual - Section 16 regarding the procedures for addressing evidence discrepancies)

The analyst will include a general description of the submitted evidence. The description will include the type of container and its contents. Abbreviated descriptions (i.e.: OSEE = One Sealed Evidence Envelope) may be used in the description. Abbreviated descriptions must be interpretable by other staff Chemists.

4. Sealed Package Weight

Sealed Package Weight = the sealed package weight (SPW) is the weight including the envelope, box, etc. containing the evidence.

The sealed package weight will be recorded in the case notes. Reconciliation action must be taken if, at the time of analysis, the evidence seals are not intact and SPW of the sample differs from the weight at the time of submission by:

1. Greater than 0.1 gram on items that weigh less than one gram

2. Greater than 0.2 gram on items that weigh between 1.0 and 10.0 grams

3. Greater than 2 % on items that weigh more than 10.0 grams.

NOTE: Due to the nature of plant material and mushrooms and their susceptibility to dehydration, if the difference in sealed package weight is greater than 5%, reconciliation of the difference will be accomplished before the analysis is begun.

No testing will be conducted until another analyst reviews packaging integrity or reconciliation between the analyst and the submitter (or their representative) is accomplished.

GENERAL OBSERVATIONS (continued)

5. Gross Weight (if applicable)

Note: If the nature of the sample requires a net weight to be obtained, then (if possible) a gross weight will also be obtained.

Gross Weight = Gross weight will include any packaging directly touching the suspected drug.

Prior to beginning analysis, a gross weight of the drug submission will be obtained and written in the case notes.

B. ANALYSIS

1. Net Weight

Net Weight = the net weight is the weight of the drug specimen that includes no packaging.

The net weight of the drug sample will be obtained after removal of the drug from the package. The analyst should remove any extraneous debris from the sample prior to obtaining the net weight.

2. Evidence Sampling Plan - minimum requirements

The evidence sampling requirements should be detailed at the time of submission or upon conference with the investigating officer or representative from the prosecutor’s office (District Attorney/Attorney General).

When no specific sampling instructions have been provided by the client for cases involving multiple similar samples, sampling decisions are made based on statistically valid methods that are recommended/accepted by major peer institutions (such as SWGDRUG, DEA or ASTM) that issue guidelines in this regard. The plan of such sampling is available in the Controlled Substances procedures manual and is readily available to the analysts.

When the customer requests deviations, additions or exclusions from the sampling Test Method, it shall be recorded in the case record with appropriate sampling data and test results.

The case record will either explain the sampling procedures, or will reference the procedures/client consultations in this regard.

The following is a suggested Evidence Sampling Plan for multiple evidence submissions:

When receiving evidence which consists of a number of packages of drugs (plant material, powder, "chunks", etc.) it may not be necessary to analyze every container of evidence. In the interest of time and expense a statistically valid number of samples can be chosen for analysis. The following table is from the DEA Laboratory Operations Manual and shows the number of representative samples to be analyzed from a large number of homogeneous samples if all samples are expected to be positive for a drug. Evidence submissions will be subjected to an appropriate screening test.

For example, if the submission consists of one hundred (100) packages of off-white powder, which have the same appearance, and all of the samples are expected to contain a drug:

1] Obtain gross weight of all 100 vials

2] Choose 25 vials at random (following sampling plan)

3] Obtain Net Weight and conduct screen test for all 25 vials

4] Use the weight of all 25 samples and extrapolate for all 100 vials

5] If all 25 samples screen positive – composite all 25 samples, grind to

homogenous mixture and run confirmation

Extrapolation of Weight:

Total # of items submitted

Total Net Weight = --------------------------------------- X Total Net Weight of Items Tested

Total # of Items tested

Evidence Sampling Plan (continued)

SUGGESTED EVIDENCE SAMPLING PLAN

|Total Number of Containers or Dosage Units |Containers or Dosage Units Tested |

| ................
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