Summary & Overview

CPT 0394U: PFAS Testing & PFASure™ Serum/Plasma LC–MS/MS

CPT code 0394U designates a Proprietary Laboratory Analyses (PLA) test — PFAS Testing & PFASure™ from National Medical Services, NMS Labs Inc. The assay quantifies 16 perfluoroalkyl substances (PFAS) in serum or plasma using LC–MS/MS, and is used in clinical and environmental exposure assessments. As a PLA code, 0394U applies uniquely to this manufacturer’s test and is relevant for clinicians, laboratories, and payers managing PFAS-related diagnostic requests nationwide.

Key payers discussed include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of clinical context for PFAS biomonitoring, where the service is typically performed, and payer coverage landscape. The publication summarizes benchmarks for utilization and reimbursement where available, highlights coding and billing considerations tied to PLA status, and outlines policy and coverage themes that affect access to specialized PFAS testing across commercial and public payers.

This summary is intended to inform stakeholders about the function and significance of CPT code 0394U, how it is used in practice for PFAS exposure evaluation, and what topics to expect in the full analysis, including payer approaches, billing guidance, and clinical applicability.

AetnaBlue Cross Blue ShieldCigna HealthUnitedHealthcareMedicare0394UCPTProprietary Laboratory AnalysesPFAS testingPFASureLC-MS/MSlaboratory diagnosticsenvironmental exposure

Billing Code Overview

CPT code 0394U is a Proprietary Laboratory Analyses (PLA) code for PFAS Testing & PFASure™ performed by National Medical Services, NMS Labs Inc. The test measures the levels of 16 perfluoroalkyl substances (PFAS) compounds in a serum or plasma specimen using liquid chromatography with tandem mass spectrometry (LC–MS/MS).

Service type: Commercial laboratory diagnostic testing for environmental/toxicology exposure assessment
Typical site of service: Clinical laboratory or specialized reference lab (specimen collected in outpatient phlebotomy or clinical setting and sent to the performing laboratory)

Clinical & Coding Specifications

Clinical Context

A typical patient is an adult or pediatric patient with documented or suspected exposure to per- and polyfluoroalkyl substances (PFAS) from an environmental source (contaminated drinking water, occupational exposure, firefighting foam, or nearby industrial release). The patient presents to an outpatient specialty clinic (occupational medicine, environmental health, toxicology, or primary care) requesting confirmatory serum testing after exposure history and counseling. The clinician orders PFAS quantitative serum testing using the PFASure™ panel performed by NMS Labs (Proprietary Laboratory Analysis 0394U). A phlebotomy visit is scheduled at an outpatient laboratory or hospital outpatient draw station. A serum or plasma specimen is collected, processed, and shipped under chain-of-custody and stability requirements to the performing laboratory. Results report concentrations of 16 PFAS compounds measured by liquid chromatography–tandem mass spectrometry (LC–MS/MS). Reported values inform exposure assessment, patient counseling, occupational case management, or public health reporting. Typical sites of service include outpatient laboratory draw sites, hospital outpatient phlebotomy, occupational health clinics, and outpatient specialty clinics. Follow-up actions (clinical interpretation, additional testing, or public health notification) occur in outpatient or consultative visits after results are returned.

Coding Specifications

Modifier	Description	When to Use
`00`

Taxonomy Code	Specialty	Notes
`207Q00000X`	Occupational Medicine	Common ordering specialty for PFAS exposure assessment.
`207L00000X`	Environmental Medicine / Toxicology	Specialists in environmental exposure and toxicant assessment.
`207K00000X`	Internal Medicine	Primary care physicians managing exposure-related follow-up.
`208D00000X`	Emergency Medicine	May order testing in acute exposure investigations or triage situations.
`207P00000X`	Preventive Medicine	Public health or preventive clinicians coordinating exposure screening.

Related Diagnoses

ICD-10 Code	Description	Clinical Relevance
`Z77.22`	Contact with and (suspected) exposure to per- and polyfluoroalkyl substances (PFAS)	Direct exposure code indicating patient contact with PFAS; primary rationale for ordering `0394U`.
`Z57.8`	Occupational exposure to other specified agents	Used when exposure is work-related and further specified as PFAS in documentation.
`Z71.89`	Other specified counseling	For documented exposure counseling sessions accompanying testing.
`R68.89`	Other general symptoms and signs	When nonspecific symptoms prompt environmental exposure testing.
`T45.9X5A`	Poisoning by unspecified drugs, medicaments and biological substances, initial encounter	Used in cases where PFAS exposure is coded under toxic effect framework for acute exposures (apply appropriate toxin code as clinically justified).

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`36415`	Collection of venous blood by venipuncture	Commonly performed immediately before `0394U` to obtain serum or plasma specimen for PFAS testing.
`36416`	Collection of capillary blood specimen (e.g., finger, heel)	Alternative specimen collection method when venipuncture is not feasible (pediatric or difficult access patients), though serum/plasma is preferred.
`99000`	Handling and/or conveyance of specimen for transfer to a laboratory	Used when additional specimen handling or special courier services are billed in conjunction with specialized PFAS testing.
`99058`	Locker rental or holding area (specimen storage)	Ancillary code used by some facilities for extended specimen storage prior to shipment (payer-dependent).
`81162`	Tumor genetics testing (example molecular)	Represents advanced laboratory-based testing codes that may be billed alongside specialized PLA codes in complex laboratory workflows; listed here as an example of specialized testing coordination.