c. Wetting Agent Fume Suppressants (WAFS). 

 The MACT standard allows the use of WAFS as a compliance 

alternative for meeting the applicable emission limit. WAFS are 

used in most decorative chromium electroplating and chromium 

anodizing tanks and in many hard chromium electroplating tanks 

for emission control. Historically, the most effective types of 

WAFS have been based on perfluorooctyl sulfonate (PFOS). The 

PFOS-based WAFS used in the chromium electroplating industry are 

part of a family of chemical compounds categorized as long-chain 

perfluorinated chemicals (PFC). As noted in a 2010 California 

Office of Health Hazard Assessment report, Perfluorooctane 

sulfonate (PFOS) and Its Salts and Transformation and 

Degradation Precursors,2 these compounds have persistent, 

bioaccumulative, and toxic characteristics and are a particular 

concern for children’s health. Although it has not been 

demonstrated that these compounds cause adverse effects to 

humans, studies have shown significant adverse effects to 

laboratory animals, wildlife, and groundwater. 

Over the last several years there have been developments 

associated with the use of WAFS as a compliance alternative. 

There are now several types of WAFS on the market that do not 

 

2 This report is available at 

http://www.oehha.org/prop65/CRNR_notices/pdf_zip/070910_PFOS_CIC.pdf

Comment [cjh1]: Suggest 

deletion, since that SAB 

report does not make 

reference to the health 

effects of PFOS. The report 

is about PFOA. 

Deleted: a 2006 EPA SAB 

report, SAB Review of EPA’s 

Draft Risk Assessment of 

Potential Human Health 

Effects Associated with PFOS

and Its Salts1 and also in 

Comment [cjh2]: Can you 

please provide citations? 

Deleted: cost-effective 
include PFOS chemicals and have been proven effective for use in 

hard chromium and decorative chromium electroplating baths that 

we believe are cost-effective. Furthermore, these non-PFOS WAFS 

are not associated with any known adverse health effects. 

Although the non-PFOS WAFS have not been used extensively in the 

chromium anodizing industry, we are not aware of any technical 

reasons to preclude their use and effectiveness for chromium 

anodizing baths. However, we seek comment on this, as well as 

on our assessment that their use is cost-effective. Because of 

the adverse non-air quality health and environmental impacts 

associated with using PFOS-based WAFS (i.e., concern over the 

presence of long-chain PFC in the environment), we are proposing 

under CAA section 112 (d)(6) to revise the scope of the 

compliance alternative to no longer allow the addition of PFOSbased WAFS to tanks as a control method for these source 

categories. We solicit comment on all aspects of this change, 

including the non-air quality health and environmental impacts 

associated with using PFOS based WAFS.

For new sources, we are proposing that no PFOS-based WAFS 

could be used effective upon startup. For existing sources, we 

are proposing that no PFOS-based WAFS could be added to the 

electroplating or anodizing tanks beginning 3 years after 

promulgation of the final amendments; however, the tanks may 

continue operating with the remaining PFOS-based WAFS in them 

Deleted: the increasing 
after that date until it is depleted. Under these amendments, 

these requirements would be specified in 40 CFR 63.342(c)(1)(iv) 

and (2)(vi) for hard chromium electroplating tanks, 40 CFR 

63.342(d)(3) for decorative chromium electroplating and chromium 

anodizing tanks, and 40 CFR 63.342(e)(2) for decorative chromium 

electroplating tanks that use a trivalent chromium bath. A 

definition of PFOS-based fume suppressants also would be added 

to 40 CFR 63.341.