T52.821 – Toxic effect of cycloparaffins, accidental (unintentional)

ICD-10-CM 2027 diagnosis code · Toxic effects of substances chiefly nonmedicinal as to source

Non-billable header New in 2027

ICD-10-CM code T52.821

Code: T52.821 (claims format: T52821)
Description: Toxic effect of cycloparaffins, accidental (unintentional)
Billable: No – use a more specific code below
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 19. Injury, poisoning and certain other consequences of external causes (S00-T88)
Block: T51-T65 Toxic effects of substances chiefly nonmedicinal as to source
Parent codes: T52 › T52.8 › T52.82

Billable codes under T52.821

T52.821 is a header code and cannot be used on claims. Choose the most specific code:

T52.821A – Toxic effect of cycloparaffins, accidental (unintentional), initial encounterBillable · New in 2027
T52.821D – Toxic effect of cycloparaffins, accidental (unintentional), subsequent encounterBillable · New in 2027
T52.821S – Toxic effect of cycloparaffins, accidental (unintentional), sequelaBillable · New in 2027

7th character values

Codes in this category need a 7th character to describe the encounter or episode of care.

Character	Meaning
`A`	initial encounter
`D`	subsequent encounter
`S`	sequela

Notes for T52.821

Applicable to:

Toxic effects of cycloparaffins NOS

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

T52 – Toxic effect of organic solvents

Excludes1 (not coded here):

halogen derivatives of aliphatic and aromatic hydrocarbons (T53.-)

7th character note:

The appropriate 7th character is to be added to each code from category T52

T52.82 – Toxic effects of cycloparaffins

Applicable to:

Toxic effects of naphthenes
Toxic effects of cycloalkanes

Block T51-T65

Excludes1 (not coded here):

contact with and (suspected) exposure to toxic substances (Z77.-)

Use additional code:

code(s):
for all associated manifestations of toxic effect, such as: respiratory conditions due to external agents (J60-J70)
personal history of foreign body fully removed (Z87.821)
to identify any retained foreign body, if applicable (Z18.-)

Notes:

When no intent is indicated code to accidental. Undetermined intent is only for use when there is specific documentation in the record that the intent of the toxic effect cannot be determined.

Related codes in T52.82

Frequently asked questions

What is ICD-10 code T52.821?

T52.821 is the ICD-10-CM code for toxic effect of cycloparaffins, accidental (unintentional), in the block T51-T65 (Toxic effects of substances chiefly nonmedicinal as to source).

Is T52.821 a billable code?

No. T52.821 is a header code with more specific child codes; report one of the billable codes listed above.

What category does T52.821 belong to?

It belongs to category T52 – Toxic effect of organic solvents.

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.