Z77.121 – Contact with and (suspected) exposure to harmful algae and algae toxins
ICD-10-CM 2027 diagnosis code · Persons with potential health hazards related to family and personal history and certain conditions influencing health status
- Code
Z77.121(claims format:Z77121)- Description
- Contact with and (suspected) exposure to harmful algae and algae toxins
- Short description
- Contact w and exposure to harmful algae and algae toxins
- Billable
- Yes – valid for HIPAA-covered transactions
- Valid for
- Dates of service October 1, 2026 – September 30, 2027 (FY2027)
- Chapter
- 21. Factors influencing health status and contact with health services (Z00-Z99)
- Block
- Z77-Z99 Persons with potential health hazards related to family and personal history and certain conditions influencing health status
- Parent codes
- Z77 › Z77.1 › Z77.12
Notes for Z77.121
- Contact with and (suspected) exposure to (harmful) algae bloom NOS
- Contact with and (suspected) exposure to blue-green algae bloom
- Contact with and (suspected) exposure to brown tide
- Contact with and (suspected) exposure to cyanobacteria bloom
- Contact with and (suspected) exposure to Florida red tide
- Contact with and (suspected) exposure to pfiesteria piscicida
- Contact with and (suspected) exposure to red tide
Notes inherited from parent codes
Instructional notes at a category or block level apply to every code below it.
Z77 – Other contact with and (suspected) exposures hazardous to health
- contact with and (suspected) exposures to potential hazards to health
- contact with and (suspected) exposure to communicable diseases (Z20.-)
- exposure to (parental) (environmental) tobacco smoke in the perinatal period (P96.81)
- newborn affected by noxious substances transmitted via placenta or breast milk (P04.-)
- occupational exposure to risk factors (Z57.-)
- retained foreign body (Z18.-)
- retained foreign body fully removed (Z87.821)
- toxic effects of substances chiefly nonmedicinal as to source (T51-T65)
Block Z77-Z99
Index terms for Z77.121
Entries in the ICD-10-CM alphabetic index that lead to this code:
- Contact, red tide
- Exposure, red tide
- Contact, brown tide
- Contact, algae bloom
- Exposure, brown tide
- Exposure, algae bloom
- Contact, cyanobacteria bloom
- Contact, pfiesteria piscicida
- Exposure, cyanobacteria bloom
- Exposure, pfiesteria piscicida
- Contact, algae and algae toxins
- Contact, blue-green algae bloom
- Exposure, algae and algae toxins
- Exposure, blue-green algae bloom
Related codes in Z77.12
- Z77.120 – Contact with and (suspected) exposure to mold (toxic)Billable
- Z77.122 – Contact with and (suspected) exposure to noiseBillable
- Z77.123 – Contact with and (suspected) exposure to radon and other naturally occurring radiationBillable
- Z77.128 – Contact with and (suspected) exposure to other hazards in the physical environmentBillable
Frequently asked questions
What is ICD-10 code Z77.121?
Z77.121 is the ICD-10-CM code for contact with and (suspected) exposure to harmful algae and algae toxins, in the block Z77-Z99 (Persons with potential health hazards related to family and personal history and certain conditions influencing health status).
Is Z77.121 a billable code?
Yes. Z77.121 is a billable/specific code that can be used to indicate a diagnosis for reimbursement purposes.
What category does Z77.121 belong to?
It belongs to category Z77 – Other contact with and (suspected) exposures hazardous to health.
Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.