Sodium Hypochlorite Supply Chain - Executive Summary

Sodium Hypochlorite

Direct Use Chemical


Inputs to Manufacturing Process:

Sodium Hydroxide

J* Derivative Water Treatment Chemicals:


% of Total Domestic Consumption
Attributed to Water Sector:

Less than 10%

(^Understanding Chemical Supply Chains
Map of Suppliers & Manufacturers

A. Product Family:

CAS No.:

K Shelf Life:
1 Month

— RISK OF SUPPLY DISRUPTION (Assessed in 2022)

RISK RATING: Moderate-High


Low Mo den

Ra"ge 'S/>


Production of sodium
hypochlorite depends on the
chlor-alkali industry to produce
the inputs used to manufacture
it. Unplanned and planned
reductions in chlor-alkali
production capacity have
reduced the supply of sodium


Criticality: High. Essential for
water disinfection.

Likelihood: High. Previous
widespread disruptions in supply
that impacted the water sector.

Vulnerability: Low. Distributed
domestic manufacturing and


Water Treatment Uses


Domestic Manufacturing Locations (2015):
91, distributed throughout the U.S.

(^) International Trade (2019)

PrimaryTrading Partner (Imports): Canada
PrimaryTrading Partner (Exports): Canada

Domestic Consumption (2015):
962 Million kg

¦	Domestic Production (866 M kg)

¦	Imports for Consumption (110 M kg)

¦	Export of Domestic Production (15 M kg)


Sodium Hypochlorite Supply Chain - Full Profile

Product Description

Sodium hypochlorite (NaOCI), an inorganic chemical and strong oxidant, is a widely used water disinfectant. It is
a derivative product of the chlor-alkali industry, primarily manufactured through the reaction of sodium
hydroxide solution with chlorine. The majority of sodium hypochlorite manufactured in the U.S. is used in
cleaning and general disinfection applications.

Use in Water Treatment

Sodium hypochlorite has several uses in water treatment, including primary and residual disinfection, algal
control, and on-site generation of chlorine dioxide (AWWA, 2018).

Use as a Precursor to Other Water Treatment Chemicals

Sodium hypochlorite is not used to manufacture other water treatment chemicals.

Other Applications

Sodium hypochlorite is widely used in many industries and a variety of settings as a general disinfectant and
bleaching agent. It is also used in semiconductor manufacturing, and formulating pesticides, fungicides, and
algicides (NCBI, 2020).

Primary Industrial Consumers

Sodium hypochlorite is primarily used for cleaning and disinfection across a wide range of industries and

Manufacturing, Transport, & Storage

Manufacturing Process

Chlorine and sodium hydroxide are the most common starting materials used to produce sodium hypochlorite,
as illustrated by the equation shown in Figure 1. The production of sodium hypochlorite is often co-located at
chlor-alkali manufacturing facilities where chlorine and sodium hydroxide are produced. Sodium hypochlorite is
also produced in facilities designed specifically for its production, which procure chlorine and sodium hydroxide
from chlor-alkali manufacturing facilities or their distributors. Manufacturing takes place by one of two
methods: the batch method or continuous method. The continuous method is more prevalent in domestic
manufacturing. In the continuous process, gaseous chlorine is injected into a dilute sodium hydroxide solution.
The automated continuous process avoids over-chlorination and leads to production of a stable solution by
controlling the ratio of chlorine to sodium hydroxide to allow for excess sodium hydroxide that is necessary to
stabilize the final solution. Sodium hypochlorite and sodium chloride are produced in equal amounts in addition
to water through this reaction (Olin Corporation, 2019; NCBI, 2020; The Chlorine Institute, 2017). The general
equation for this process is shown in Figure 1.


+ Sodium Hydroxide —

> Sodium Hypochlorite +

Sodium Chloride +



+ 2NaOH

¦> NaOCI +

NaCI +


Figure 1. Chemical Equation for the Reaction to Manufacture Sodium Hypochlorite

Additionally, sodium hypochlorite can be produced using a "brine to bleach" process, which uses electrolysis of
brine in a process similar to that used by the chlor-alkali production facilities (Odyssey Manufacturing, 2022).
However, the majority of sodium hypochlorite produced for the commercial market occurs using the process
described in Figure 1.

EPA 817-F-22-047 | December 2022


Sodium Hypochlorite Supply Chain - Full Profile

While most sodium hypochlorite used in water treatment is manufactured off-site, some water treatment
facilities choose to generate sodium hypochlorite onsite. The process for onsite generation requires sodium
chloride and softened or deionized water to produce a brine that is passed through an electrolytic cell to
generate sodium hypochlorite. The sodium hypochlorite is then stored in a separate tank and metered into the
water (PSI Water Technologies, 2020).

Product Transport

The geographic market for distribution is limited by the expense of transporting sodium hypochlorite. Generally,
the maximum distance for truck transport considered to be economically efficient is approximately 250-300
miles from the point of production (FTC, 2013). Bulk transport by rail is very significant and allows for
manufacturing locations to meet wide geographic distribution (Olin Corporation, 2019).

Storage and Shelf Life

Sodium hypochlorite solution should be stored in tightly closed containers and kept in a cool place away from
the direct sunlight. When stored properly, sodium hypochlorite can have a shelf life of approximately 1 month,
depending on temperature, pH, concentration, presence of impurities, and size of storage container. Storage
durations beyond recommended shelf life can lead to product degradation and loss of efficacy (Olin Corporation,
2019; CDC, 2014).

Domestic Production & Consumption

Domestic Production

Production data was collected from the 2016 EPA Toxic Substances Control Act (TSCA) Chemical Data Reporting
(CDR) for the year 20151, while trade data was collected from the U.S. International Trade Commission (USITC)
Dataweb, as shown in Table 1. While production data is specific to sodium hypochlorite, trade data includes
sodium hypochlorite as part of the category for hypochlorites, chlorites, and hypobromites.

Table 1. Sodium Hypochlorite Production and Trade Data Sources

Production and Trade Data


Data Source and Date



Domestic Production

2020 TSCA Chemical Data Reporting

CAS No.: 7681-52-9

Sodium Hypochlorite

Imports and Exports

U.S. International Trade Commission

HS Code: 2828.90

Hypochlorites, Chlorites, and

Total U.S. domestic manufacturing of sodium hypochlorite reported under the CDR was approximately 886
million kilograms (M kg) in 2015; however, several leading manufacturers (i.e., Olin, Univar) claimed confidential
business information and did not report production volumes to EPA (EPA, 2016). Domestic commercial
manufacture of sodium hypochlorite takes place at many facilities located throughout the contiguous U.S.,
including chlor-alkali facilities, traditional bleach production facilities, and brine-to-bleach facilities. Thus, there
are more production locations for sodium hypochlorite than there are production locations for chlor-alkali
chemicals. Most sodium hypochlorite production facilities rely on the availability of the chlor-alkali co-products
chlorine and sodium hydroxide. The number of domestic manufacturing locations shown in Figure 2 represents
operating facilities as of 2019 (The Chlorine Institute, 2020). Supply of NSF/ANSI Standard 60 certified sodium
hypochlorite for use in drinking water treatment is widely distributed throughout the U.S. (NSF International,

1 Although 2019 CDR data is available, reporting is less complete when compared to 2015 data due to an increase in the number of
companies claiming confidential business information (CBI). In both instances, CBI may account for a significant volume of sodium
hypochlorite produced that is not reflected in CDR reporting.



Sodium Hypochlorite Supply Chain - hull Profile

2021). For a more current listing of manufacturing locations and supplier locations, visit the U.S. Environmental
Protection Agency's (EPA's) Chemical Locator Tool (EPA, 2022a).







O  ® # Qr

%O «



i)0 Q)>



Domestic Supply and Manufacturing of Sodium Hypochlorite
O 216 NSF/ANSI Standard 60 Certified Suppliers (NSF International, 2021)

91 Domestic Manufacturing Locations (The Chlorine Institute, 2020)

^ 'c-S«' T- into.*

Figure 2. Domestic Supply and Manufacturing of Sodium Hypochlorite
Domestic Consumption

U.S. consumption of sodium hypochlorite in 2015 is estimated at 962 M kg. This estimate includes production of
866 M kg, import of 110 M kg, minus export of 15 M kg (EPA, 2016; USITC, 2021), as shown in Figure 3. Imports
and exports represent small quantities when compared to domestic production.

Domestic Consumption (2015):
962 Million kg

¦	Domestic Production (866 M kg)

¦	Imports for Consumption (110 M kg)

¦	Export of Domestic Production (15 M kg)

Figure 3. Domestic Production and Consumption of Sodium Hypochlorite in 2015



Sodium Hypochlorite Supply Chain - Full Profile

Trade & Tariffs

Worldwide Trade

Worldwide import and export data for sodium hypochlorite are reported through the World Bank's World
Integrated Trade Solutions (WITS), as a category representing a class of compounds including hypochlorites,
chlorites, and hypobromites. In 2021, the U.S. ranked eighth worldwide in total exports and first in total imports
of hypochlorites, chlorites, and hypobromites. In 2021, China ranked first worldwide in total exports (WITS,
2022), as shown in Table 2. Import and export data specific to sodium hypochlorite is unavailable from the
referenced sources.

Table 2. WITS Worldwide Export and Import of Hypochlorites, Chlorites, and Hypobromites, Including Sodium
Hypochlorite, in 2021

2021 Worldwide Trade
Hypochlorites, Chlorites, and Hypobromites (HS Code 2828.90)

Top 5 Worldwide Exporters

Top 5 Worldwide Importers


156 M kg

United States

133 M kg


131 M kg


74 M kg


87 M kg


56 M kg


83 M kg


54 M kg


72 M kg


47 M kg

Domestic Imports and Exports

Domestic imports and export data are reported by USITC in a category including all hypochlorites, chlorites, and
hypobromites. Figure 4 summarizes imports for consumption2 and domestic exports3 of hypochlorites, chlorites,
and hypobromites between 2015 and 2020. During this period, the overall quantity of exports and imports
remained relatively steady, with imports for consumption exceeding domestic exports. Over this five-year
period, Canada was the primary recipient of domestic exports and the primary source of imports (USITC, 2021).

2	Imports for consumption are a subset of general imports, representing the total amount cleared through customs and entering
consumption channels, not anticipated to be reshipped to foreign points, but may include some reexports.

3	Domestic exports are a subset of total exports, representing export of domestic merchandise which are produced or manufactured in
the U.S. and commodities of foreign origin which have been changed in the U.S.


Sodium Hypochlorite Supply Chain - Full Profile


1 AC\

Domestic Trade of Hypochlorites, Chlorites, and Hypobromites
HTS Code 2828.90



1 nn













" An






— 20









Sodium Hypochlorite Supply Chain - Full Profile

have a direct impact on the availability of chlorine and derivative products available for domestic consumption,
since imports represent a small fraction of overall chlorine consumption (Kreuz et al., 2022). This was
exemplified by decreased allocations of chlorine and sodium hypochlorite for drinking water and wastewater
systems in California, Oregon, Washington, Alaska, Utah, Missouri, Ohio, Pennsylvania, New York,

Massachusetts, Louisiana, and Florida, as reported directly to EPA.

A threatened rail carrier work stoppage in September 2022 highlighted the dependence of the domestic chlorine
supply chain on a complex national rail network for producers, suppliers, and end-users. Due to the
concentration of chlor-alkali facilities along the Gulf Coast combined with widespread need for chlorine, long-
distance transport of chlorine is often required. Additionally, a significant number of domestic manufacturers of
derivative water treatment chemicals are almost exclusively reliant on rail delivery of chlorine for production
needs (Branscomb et al., 2010).

Risk Evaluation

The complete risk evaluation methodology is described in Understanding Water Treatment Chemical Supply
Chains and the Risk of Disruptions (EPA, 2022b). The risk rating is calculated as the product of the following three
risk parameters:

Risk = Criticality x Likelihood x Vulnerability
Criticality	Measure of the importance of a chemical to the water sector

Likelihood Measure of the probability that the chemical will experience a supply disruption in the
future, which is estimated based on past occurrence of supply disruptions

Vulnerability Measure of the market dynamics that make a chemical market more or less resilient to
supply disruptions

The individual parameter rating is based on evaluation of one or more attributes of the chemical or its supply
chain. The ratings and drivers for these three risk parameters are shown below in Table 4.



Table 4. Supply Chain Risk Evaluation for Sodium Hypochlorite

Risk Parameter Ratings and Drivers

Sodium Hypochlorite Supply Chain - Full Profile

Criticality	High

Sodium hypochlorite is essential and
has widespread application as a
disinfectant in both drinking water
and wastewater treatment.

Likelihood	High

The water sector has experienced
widespread sodium hypochlorite
supply disruptions in the past. In 2021
disruption in the supply of sodium
hypochlorite occurred due to an
increase in demand due to the COVID-
19 pandemic and a decrease in supply
of precursors (primarily chlorine) as a
result of both temporary losses in
chlor-alkali production capacity due to
equipment failures and extreme
weather events, and permanent,
planned reductions in production

Vulnerability	Low

Strong domestic manufacturing
capabilities and a distributed
manufacturing base provide some
resilience to supply disruptions.
However, chlor-alkali facility closures
in 2021 and the potential for future
losses in production capacity could
increase vulnerability.

Risk Rating: Moderate-High

te-Low Modern

Rsnge '#4

( ^Vi


American Water Works Association (AWWA), 2018. B300, Hypochlorites. Denver, CO: American Water
Works Association.

Branscomb, L., Fagan, M., Auerswald, P.E., Ellis, R. and Barcham, R., 2010. Rail Transportation of Toxic

Inhalation Flazards: Policy Responses to the Safety and Security Externality. Flarvard Kennedy School of
Government. Retrieved from UTC20 working paper

Center for Disease Control (CDC), 2014. Frequently Asked Questions (FAQs) about Sodium Hypochlorite
Solution(SH), retrieved from

faq.html?CDC AA

EPA, 2016. 2016 TSCA Chemical Data Reporting, retrieved from

EPA, 2022a. Chemical Suppliers and Manufacturers Locator Tool, retrieved from

EPA, 2022b. Understanding Water Treatment Chemical Supply Chains and the Risk of Disruptions, retrieved



Sodium Hypochlorite Supply Chain - Full Profile


Federal Trade Commission (FTC), 2013. Federal Trade Commission: Decisions, Findings, Opinions, and
Orders. Volume 155, retrieved from decision volumes/volume-
155/decvol 155.pdf

National Center for Biotechnology Information (NCBI), 2020. PubChem Compound Summary for CID

23665760, Sodium Hypochlorite, retrieved from

NSF International, 2021. Search for NSF Certified Drinking Water Treatment Chemicals, retrieved from

Odyssey Manufacturing, 2022. UltraChlor™: Exceptional Quality, retrieved from

Olin Corporation, 2019. Sodium Hypochlorite Product Stewardship Manual, retrieved from Olin-Sodium-Hypochlorite-

Powder & Bulk Solids, 2021. "Olin to Cut Chlor Alkali Capacity at Alabama Plant," Powder & Bulk Solids,

March 16, 2021, retrieved from

Prohaska, T., 2021. "Occidental Chemical to close Niagara Falls plant; 130 jobs lost." The Buffalo News,
August 19, 2021, retrieved from
niagara-falls-plant-130-iobs-lost/article ddb5463c-010a-llec-a536-9b2a8e99ba71.html

PSI Water Technologies, 2020. City of Springfield, Missouri, Upgrades Disinfection System from Gas Chlorine
to On-Site Sodium Hypochlorite Generation, retrieved from

The Chlorine Institute, 2017. Pamphlet 96, Sodium Hypochlorite Manual, 5th Edition. The Chlorine Institute.

The Chlorine Institute, 2020. Pamphlet 10: North American Chlor-Alkali Industry Plants and Production Data
Report, Edition 2019.

The Chlorine Institute, 2021. U.S. Chlorine/Sodium Hydroxide Production and Shipment Report, September

U.S. International Trade Commission (USITC), 2021. USITC DataWeb, retrieved from

U.S. International Trade Commission (USITC), 2022. Harmonized Tariff Schedule (HTS) Search, retrieved from

World Integrated Trade Solutions (WITS), 2022. Trade Statistics by Product (HS 6-digit), retrieved from