UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

 WASHINGTON, D.C. 20460

OFFICE OF CHEMICAL SAFETY AND POLUTION PREVENTION/OFFICE OF PESTICIDE PROGRAMS 

MEMORANDUM

DATE: June 1, 2012

SUBJECT: Preliminary Human Health Assessment for the Registration Review of Potassium 

bicarbonate and Sodium bicarbonate

Registration Review Case #: 4048

PC Code: 07358, 073505

CAS #: 298-14-6, 144-55-8

Chemical Class: Biochemicals

FROM: Sadaf Shaukat, Biologist

Biochemical Pesticides Branch

Biopesticides & Pollution Prevention Division (7511P)

TO: Leonard Cole, Regulatory Action Leader

Biochemical Pesticides Branch

Biopesticides & Pollution Prevention Division (7511P)

THE FOLLOWING CONTAINS CONFIDENTIAL BUSINESS INFORMATION 

ACTION REQUESTED

The following is a preliminary human health assessment for Potassium bicarbonate and Sodium 

bicarbonate in support of the development of the Registration Review Work Plan. 
 

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RECOMMENDATIONS AND CONCLUSIONS

Executive Summary

Based on the available data and information, the Agency does not foresee the need for new data 

or for a new human health risk assessment for these active ingredients. Hazard and exposure 

information as well as Agency risk assessments on Potassium bicarbonate and Sodium 

bicarbonate were evaluated against current safety standards established by the Agency’s scientific 

policies and regulations and it was determined that there is no need to conduct an additional 

human health risk assessment. These two compounds are found throughout nature in living 

systems and in non-living environments. They are an integral part of humans, other animals, 

plants, and virtually all living organisms, and are crucial for normal function. They are also 

present in soils, water, rocks, and other parts of the environment. They are found in many

consumer products. Both compounds degrade rapidly into non-toxic components. There is 

reasonable certainty that no harm will result to the general population from exposure to these 

bicarbonates in the products containing them as active ingredients when they are used according 

to label instructions. 

 

I. Background

Products containing Potassium or Sodium bicarbonate as the active ingredient are being used as 

fungicides. Currently, there are eight products that are registered with BPPD containing 

Potassium bicarbonate as the active ingredient. Three out of the eight products are technical 

grade active ingredients (TGAI). There is one TGAI registered with BPPD containing Sodium 

bicarbonate.

II. Tolerances

§ 180.1177 Potassium bicarbonate; exemption from the requirement of a tolerance.

The biochemical pesticide potassium bicarbonate is exempted from the requirement of a 

tolerance in or on all raw agricultural commodities when applied as a fungicide or post-harvest 

fungicide in accordance with good agricultural practices.

[61 FR 67473, Dec. 23, 1996]

§ 180.1176 Sodium bicarbonate; exemption from the requirement of a tolerance.
 

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The biochemical pesticide sodium bicarbonate is exempted from the requirement of a tolerance 

in or on all raw agricultural commodities when applied as a fungicide or post-harvest fungicide in 

accordance with good agricultural practices.

[61 FR 67473, Dec. 23, 1996]

III. Incidents

There were no incidents reported from the use of products containing Sodium bicarbonate. There 

were five incidents reported from the use of products containing Potassium bicarbonate. No 

details were reported to the Agency involving incidents from the use of the Potassium 

bicarbonate products. 

IV. Toxicity Profile

Potassium bicarbonate and Sodium bicarbonate area naturally-occurring substances and are not 

expected to have adverse effects on human health. All toxicology data requirements have been 

satisfied and it is unlikely that any additional data will be required. Toxicology data and or 

rationale to fulfill or waive these requirements are available on the currently registered EPs; all of 

which indicate that these products are of low toxicity. 

Please see the tables below for detailed information regarding the toxicity data requirements.

Available toxicity data as required by 40 CFR 158.2050 regarding Potassium and Sodium 

bicarbonate are summarized below in Tables 1-7.

Table 1. Potassium and Sodium bicarbonate: Acute Oral Toxicity/OPPTS 870.1100

Active Ingredient LD50 Toxicity Category MRID

Potassium bicarbonate 2900 mg/kg (males)

2600 mg/kg (females)

2700 mg/kg (sexes 

combined)

III 44001001

Potassium bicarbonate 3822 mg/kg (males)

2931 mg/kg (females)

3358 mg/kg (sexes 

combined)

III 44092504

Sodium bicarbonate 7937 mg/kg (males)

6618 mg/kg (females)

7334 mg/kg (sexes 

combined)

IV 43297202

Sodium bicarbonate 5000 mg/kg IV 43463104

Sodium bicarbonate 5000 mg/kg IV 43463204
 

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Table 2. Potassium and Sodium bicarbonate: Acute Dermal Toxicity/OPPTS 870.1200

Active Ingredient LD50 Toxicity Category MRID

Potassium bicarbonate 2,700 mg/kg III 44001002

Potassium bicarbonate >2020 mg/kg III 44092505

Sodium bicarbonate >2000 mg/kg* III 123051

Sodium bicarbonate >2000 mg/kg* III 43297203

Sodium bicarbonate >2000 mg/kg* III 43463105

Sodium bicarbonate >2000 mg/kg* III 43643205

*highest dose tested

Table 3. Potassium and Sodium bicarbonate: Acute Inhalation Toxicity/OPPTS 870.1300

Active Ingredient LC50 Toxicity Category MRID

Potassium bicarbonate >2.3 mg/L IV 44001006

Sodium bicarbonate 4.74 ± 1.03 mg/L IV 43297204

Table 4. Potassium and Sodium bicarbonate: Acute Eye Irritation/OPPTS 870.2400

Active Ingredient Results Toxicity Category MRID

Potassium bicarbonate Iritis cleared by day 3, 

conjunctival irritation 

cleared by day 7

III 44001004

Potassium bicarbonate Conjunctival redness and 

swelling cleared by 72 

hours

III 44092507

Sodium bicarbonate Iritis and conjunctival 

irritation cleared by day 

4

III 43297205

Sodium bicarbonate Iritis and conjunctival 

irritation cleared by day 

7

III 43463106

Sodium bicarbonate Iritis and conjunctival 

irritation cleared by day 

6

III 43463206
 

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Table 5. Potassium and Sodium bicarbonate: Acute Dermal Irritation/OPPTS 870.2500

Active Ingredient Results at 72 hrs Toxicity Category MRID

Potassium bicarbonate No irritation IV 44001003

Sodium bicarbonate Slight irritation 

cleared by 48 hours III 43297206

Sodium bicarbonate Very slight irritation 

cleared by 48 hours III 43463107

Sodium bicarbonate Very slight irritation 

cleared by 48 hours III 43463207

Table 6. Potassium and Sodium bicarbonate: Skin Sensitization/OPPTS 870.2600

Active Ingredient Results MRID

Potassium bicarbonate Not a sensitizer 44001005

Potassium bicarbonate Not a sensitizer 44092509

Sodium bicarbonate Not a sensitizer 43297207

Sodium bicarbonate Not a sensitizer 43480301

Based on the information presented above, the Agency does not foresee the need for new data or 

for a new human health risk assessment. There is reasonable certainty that no harm will result to 

the general population from exposure to Potassium or Sodium bicarbonate in the products 

containing this active ingredient when they are used according to label instructions. 

cc: S. Shaukat, L. Cole, BPPD Science Review File
 

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S. Shaukat, FT, PY-S: 6/1/12