Comments Submitted by ACC and the California Manufacturers and Technology Association

70 Pages·2013·3.49 MB·English

by  Eric Newman

[email protected] re: DPH-11-005
October 10, 2013
Office of Regulations
California Department of Public Health
1616 Capitol Avenue
Sacramento, CA 95814

Re: Comments to DPH-11-005 Regulations for Proposed Maximum Contaminant Level
for Hexavalent Chromium

Dear Office of Regulations:
The California Manufacturers and Technology Association (CMTA) and the
American Chemistry Council (ACC) appreciate the opportunity to comment on the
proposal by the California Department of Public Health (CDPH) to adopt a 10 parts per
billion (ppb) maximum contaminant level (MCL) for hexavalent chromium (Cr6) in
drinking water. CDPH considered alternative MCLs between 1 and 30 ppb and selected
10 ppb as the level that is sufficiently health protective and is technically and
economically feasible in terms of water system compliance. In arriving at this
determination, CDPH has estimated that public water systems will face additional
capital investments and ongoing operational costs of at least $156 million annually to
comply with the new standard.
In these comments, we address three issues:
1. In light of the best available science, this proposed MCL of 10 ppb Cr6 is overly
restrictive and the significant costs greatly outweigh the (theoretical) benefits.
The proposed MCL is based on the Public Health Goal (PHG) adopted by the
Office of Environmental Health Hazard Assessment (OEHHA) in July 2011. The PHG is
based on the dose-response for mouse small intestine tumors observed in a 2008
CMTA/ACC Comments to DPH-11-005
October 10, 2013
Page 2

National Toxicology Program study (the NTP Study). OEHHA applied a linear
extrapolation to this high dose animal data to estimate cancer risk for very low
exposures in humans.
Important new research investigating the mode of action for Cr6 (the MOA
Studies) provides new scientific evidence demonstrating that Cr6 has a threshold for
effects, which indicates Cr6 presents a materially different risk to public health than
assumed by OEHHA when it adopted the PHG for Cr6. The recent MOA Studies
indicate that mouse small intestine tumors occur only at high doses and that the MOA
for mouse small intestinal tumors has a threshold below which there is no increased risk
of cancer. In fact, the NTP data and the MOA research were used to derive a reference
dose (RfD) and a drinking water equivalent value of 210 ppb that is health protective for
cancer and non-cancer effects even for sensitive populations. Why 210 ppb?
Research shows that the key effect leading to tumors, excessive intestinal cell growth,
also called cell proliferation, does not occur below that level. Thus, setting a drinking
water standard below the threshold level prevents this cell growth, which in turn also
prevents tumor formation. Thus, the current California state MCL of 50 ppb for total
chromium and federal MCL of 100 ppb are well below the threshold for small intestine
cancers, even in the most sensitive human subpopulations.
Relying solely on the PHG, CDPH estimated the proposed MCL would result in
twelve theoretical cancer cases avoided per year statewide. Of these 12, 0.3 theoretical
cancer cases avoided per year would come from small water systems which, contrary to
CDPH projections, would be fully realized only after 70 years of regulatory controls.
However, given the presence of a threshold, the estimated theoretical cancer cases
avoided per year statewide associated with this proposed MCL are best described as
zero. (See Attachment 1 for our detailed comments.)

2. CDPH’s cost benefit analysis contains serious errors resulting in significant
underestimation of the costs associated with this proposed rulemaking.
Additionally, CDPH did not perform an economic feasibility analysis and thus
cannot support its claim that one was conducted.
Critical evaluation of CDPH’s cost benefit analysis by a third party expert
highlights five serious errors that resulted in significant underestimation of the costs
associated with this proposed rulemaking. When these major errors1 are corrected to

1 The analysis presented in Attachment 2 corrects quantitatively for five major errors: (1) using a benefit
model inconsistent with the OEHHA LNT risk model, (2) using the same time horizon for counting both
CMTA/ACC Comments to DPH-11-005
October 10, 2013
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meet generally accepted principles, every MCL under consideration is shown to be
economically infeasible, regardless of system size.
For example, CDPH did not calculate cancer risk reductions in a manner
consistent with the OEHHA PHG and its linear non-threshold model. CDPH’s cost
benefit analysis correctly recognized that OEHHA’s unit cancer risk estimate reflects
risk reductions accruing over a 70-year lifetime. However, it failed to adjust its cost
benefit methodology consistent with this timeframe. That is, the full benefit CDPH
expected (viz.,12 theoretical cancer cases avoided per year statewide with 0.3
theoretical cancer cases avoided per year statewide for small water systems)2 will be
achieved only after 70 years, when there is no one left in the population who has been
exposed to a combination of pre- and post-treated drinking water. This methodological
inconsistency, spreading costs out 70 years without spreading benefits out over the
same timeframe, has significant ramifications for the calculation of engineering costs
per theoretical cancer case prevented.
The bottom line is that the methodological errors in CDPH’s cost benefit analysis
artificially inflate benefits relative to costs. Thus, CDPH’s cost benefit analysis does not
provide an accurate portrayal of cost, benefits, cost-effectiveness, or economic
feasibility. Thus, legislators, decision-makers and importantly the impacted public are
misled about the likely consequences of this regulatory action.
CDPH’s cost benefit analysis is applied in Attachment 2 using the PHG as CDPH
did,3 but correcting key errors in the cost benefit analysis and adding an assessment of
the economic feasibility, which is missing from CDPH’s analysis. Attachment 2 reports
that none of the MCLs under consideration are economically feasible for households
and customers served by small water systems. In fact, all of the MCLs under
consideration impose a new income tax, i.e., an imposed cost with virtually no
corresponding benefit, on almost all Californians. This tax is especially burdensome for
those Californians in communities CDPH classifies as ‘disadvantaged’ (households with
median income less than $46,842) and ‘severely disadvantaged’ (households with
median income less than $35,132). For households in disadvantaged communities, this

costs and benefits, (3) discounting future costs but not future benefits, (4) failing to account for cessation
lags, and (5) failing to account for less-than-certain causation. One of these corrections materially
increases the cost estimate; the other four materially decrease the benefit estimate.
2 CDPH, Aug 4, 2013, Initial Statement of Reasons, see pages 24-25. Accessed at:
http://www.cdph.ca.gov/services/DPOPP/regs/Documents/DPH-11-005HCMCLISOR.pdf
3 The analysis in Attachment 2 does not attempt to portray a corrected cost benefit analysis using the
recent MOA research findings demonstrating a threshold effect.
CMTA/ACC Comments to DPH-11-005
October 10, 2013
Page 4

new income tax could claim as much as 15% of household income; for severely
disadvantaged communities, this tax could claim as much as 20% of household income.
The detailed comments in Attachment 2 elaborate on these points.

3. Contrary to CDPH statements, CDPH’s own data identifies significant direct
costs to California businesses, sufficient to qualify as a ‘major regulation.’
In the Notice of Proposed Rulemaking, CDPH asserts that the proposed regulation
would not significantly affect:
 Creation or elimination of jobs within the State of California.
 Creation of new businesses or the elimination of existing businesses within
the State of California and that the impact (costs) for the proposed regulation
would be insignificant.
 Expansion of businesses currently doing business within the State of
California.
This statement is also made in Form 399, the Economic and Fiscal Impact Statement,
and other documents supporting this proposed regulation.
CDPH clearly states that under California law, once the MCL for Cr6 is finalized,
it would apply to community water systems (CWS) and to non-transient non-community
water systems (NTNCWS). Both types of water systems would bear the costs for
sampling, and monitoring drinking water sources and applying best available technology
(BAT) treatment to each drinking water sources (e.g., each well) found to be non-
compliant. By definition, an NTNCWS is defined as, “A public water system that
regularly supplies water to at least 25 of the same people at least six months per year,
but not year-round. Some examples are schools, factories, office buildings, and
hospitals which have their own water systems.”4
Thus, California businesses that provide drinking water to their employees and
guests must comply with this regulation. CDPH includes wineries, commercial
nurseries, agricultural operations, food processors, small businesses and other facilities
within the NTNCWS category. Accordingly, these businesses would be required to
comply with the proposed Cr6 MCL. In some cases, non-compliant water systems
might seek alternative surface water supplies or other water sources, which might put

4 Definition of non-transient non-community water systems is established by the US Environmental
Protection Agency, available at: http://water.epa.gov/infrastructure/drinkingwater/pws/factoids.cfm.
CMTA/ACC Comments to DPH-11-005
October 10, 2013
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additional pressure on already limited surface water sources, such as the Sacramento-
San Joaquin Delta and the Colorado River.
CDPH provided a series of cost estimates in its cost benefit analysis5 in which it
estimates that 65 private water systems, including a number of agricultural and
industrial operators that would be impacted by a 10 ppb MCL at an annual capital and
operating cost of $28.7 million (excluding monitoring costs) out of the $156 million total
costs estimated for this rule. Based upon CDPH estimates, applied equally, each of
these 65 private entities will be burdened with an average annual cost of approximately
$442,000 per year to comply with the 10 ppb MCL.
CDPH’s estimated 65 NCNTWS could underestimate the actual number of
affected NCNTWS since the California CDPH’s 2001 unregulated contaminant
monitoring program excluded small water systems serving less than 150 service
connections (homes or individuals).6 Thus, it is very likely that CDPH based its
estimation on an incomplete database for NTNCWS. It is reasonable to assume that
additional businesses, including agricultural and industrial entities, will find themselves
subject to the full financial burden of compliance.
Even if we assume that the CDPH estimated cost of $28.7 million identified with
private water systems is correct, albeit perhaps only a partial scope of the private water
systems captured by this proposed rule, then the rule exceeds the Cal/EPA definition of
a ‘major regulation’ (greater than $10 million in annual costs). In any event, CDPH has
greatly misstated the costs to businesses.

4. Conclusion
The proposed 10 ppb MCL for Cr6 would provide no public health benefit to
Californians, but would impose an extraordinary cost burden on affected water systems
– especially on small systems – and their residential and business customers (both
homeowners and businesses). This burden would be especially heavy for
‘disadvantaged’ and ‘severely disadvantaged ‘communities, which would face a ‘new
tax’ consuming 15% and 20% (respectively) of their household income annually with no
benefit.

5 CDPH, Procedure for Cost-Benefit Analysis of Hexavalent Chromium, August 4, 2013. See tables on
pages 81-84.
6 http://www.cdph.ca.gov/certlic/drinkingwater/Pages/Chromium6sampling.aspx
CMTA/ACC Comments to DPH-11-005
October 10, 2013
Page 6

The latest science demonstrates that there is a threshold below which there is no
increased risk of cancer. In fact, this new science can be used to derive a reference
dose (RfD) and a drinking water equivalent value of 210 ppb that is health protective for
cancer and non-cancer effects even for sensitive populations. Below a 210 ppb drinking
water concentration, the research shows that the key effect identified in the NTP study
relied upon as the basis for the PHG, that is, excessive intestinal cell growth, also
known as cell proliferation, does not occur. If this cell growth is prevented, tumors will
be prevented and cancer will not occur. Thus, an MCL of 50 ppb, which is well below
the 210 ppb threshold, is health protective.
CDPH should correct the defects in its cost benefit analysis and provide a
realistic picture of the costs, benefits, and cost-effectiveness of this proposed regulation
and any other draft MCL it considers for Cr6. CDPH should conduct an economic
feasibility analysis and reissue an MCL that is both health-protective and economically
feasible.
Contrary to statements that there are ‘no significant cost to businesses,’ CDPH
data indicate some businesses would face the full burden of complying with this draft
MCL at a cost estimated by CDPH to be $28.7 million per year, which could amount to
several hundred thousand dollars per year for each business. CDPH should accurately
characterize the direct and indirect costs to businesses, which could include wineries,
commercial nurseries, agricultural operations, food processors, small businesses and
other facilities that provide drinking water to their employees and thus meet the
definition of an NTNCWS.
Legislators, politicians, decision-makers and rate-paying homeowners and
businesses should have a more accurate presentation of the facts as they weigh
whether the benefits of this proposed rule justify the costs.

Sincerely,

Ann M. Mason Michael Rogge
Senior Director Legislative Director, Environmental Health
American Chemistry Council California Manufacturers &Technology Association
700 2nd Street NE 1115 Eleventh Street
Washington, DC 20002 Sacramento, CA 95814
202.249.6704 916.498.3313
CMTA/ACC Comments to DPH-11-005
October 10, 2013
Page 7

Attachment 1: The proposed MCL of 10 ppb Cr6 is overly stringent in light of recent MOA
research identifying a threshold for effects for Cr6 in drinking water.
Attachment 2: A Review of the California Department of Public Health’s Cost-Benefit Analysis
in Support of a Proposed Primary Drinking Water Standard for Cr VI

cc:
Ronald Chapman, M.D. – Director, Department of Public Health –
[email protected]

David Mazzera – Acting Chief, Department of Public Health Division of Drinking Water and
Environmental Management – [email protected]
Attachment 1: The proposed MCL of 10 ppb Cr6 is overly stringent in light of
recent MOA research identifying a threshold for effects for Cr6 in drinking water.
Even taking CDPH’s cost estimate at face value, we strongly question the need for the
substantial investment in new treatment technology to address concentrations of Cr6
greater than 10 ppb. The latest peer-reviewed scientific research indicates that oral
ingestion of Cr6 in drinking water poses materially less risk than the estimate from the
Office of Environmental Health Hazard Assessment (OEHHA). OEHHA’s risk estimate
was developed as part of the agency’s setting of the public health goal (PHG) for Cr6 in
July, 2011.
This new research, published in a series of fourteen peer-reviewed articles,
demonstrates that mouse small intestinal tumors, the endpoint that provides the basis
for the PHG, occur only at high doses (Attachment 1A). OEHHA did not consider the
biological mechanism in developing the PHG and applied a default assumption -- linear
low-dose extrapolation -- to set the PHG at 0.02 ppb. Importantly, the new research,
designed to identify the biological mechanism, clearly demonstrate that these tumors do
not occur below a threshold concentration that is considerably higher than both the
current federal MCL of 100 ppb for total chromium and the current California MCL of 50
ppb for total chromium.
The new evidence identifying the biological activity, or mode of action (MOA),
underlying the mouse small intestinal tumors has determined that there is a threshold
for effects. Based upon this research, a reference dose and non-linear model can be
used rather than defaulting to the linear assumption for low dose extrapolation used in
OEHHA’s PHG and, by association, CDPH’s proposed MCL of 10 ppb. The new
science demonstrates that both the federal MCL of 100 ppb and the current California
MCL of 50 ppb continue to be health protective.
Furthermore, these new scientific findings show that the significant costs for treating
drinking water to the proposed MCL will not result in any health benefits, i.e., there will
not be any reductions in cancer risk despite huge costs. In fact, because there is a
threshold for effects (cancer and non-cancer) associated with Cr6 in drinking water, the
theoretical cancer risk is zero at the current federal MCL of 100 ppb, the state MCL of
50 ppb and at any concentrations lower than 210 ppb.
The High Dose NTP Study Formed the Basis for the OEHHA PHG
On July 24, 2011, OEHHA adopted a PHG for Cr6 of 0.02 ppb based on the occurrence
and dose-response of mouse small intestinal tumors observed in a 2008 National
Toxicology Program Study (the NTP Study). As noted, OEHHA applied the default
procedure of linear extrapolation to the high dose animal data developed by NTP to
estimate increased cancer risk at very low human exposures. In the NTP Study,
rodents (rats and mice) were exposed to four high doses of Cr6 in their drinking water at
concentrations ranging from 5,000 ppb to 180,000 ppb. NTP reported an increased
incidence of tumors in the small intestine of the mice exposed to concentrations above
CMTA/ACC Comments to DPH-11-005
Attachment 1
Page 9

30,000 ppb relative to historical control groups and above 60,000 ppb relative to the
NTP Study controls.
The lowest drinking water exposure level (5,000 ppb) in the NTP study was 100 times
greater than the current California MCL of 50 ppb and over 1,000 times higher than
typical levels of Cr6 in public drinking water supplies. In California, approximately one-
third of drinking water supply sources sampled contain Cr6 at low levels.7 The scientific
literature indicates that much of this “contamination” comes from naturally occurring
serpentine formations in California groundwater basins. About two-thirds of the
detectable concentrations range from 1-5 ppb, with 4 sources (out of 2,432) above the
MCL for total chromium of 50 ppb.8 According to the Agency for Toxic Substances and
Disease Registry: “Typical U.S. drinking water supplies contain total chromium levels
within a range of 0.2-35 [ppb] however, most supplies in the United States contain < 5
[ppb] of chromium.”9
In August, 2009, relying primarily upon the NTP Study, OEHHA proposed a cancer-
based PHG of 0.06 ppb.10 Although the NTP Study did not identify the biological
mechanism underlying tumor formation, OEHHA assumed that oral exposure to Cr6
caused mutations that led to heritable changes in the DNA in the mouse small
intestine—in other words, the small intestinal tumors occurred by a mechanism that
involved mutations. After making that critical initial assumption, OEHHA followed US
EPA’s 2005 Guidelines for Carcinogen Risk Assessment (hereinafter referred to as the
Cancer Guidelines); the Cancer Guidelines indicate that in the case of a mechanism
involving mutations, a linear (non-threshold) analysis should be used to evaluate the
level (or dose) at which the risk of cancer becomes negligible, usually at the very low
risk level of one-in-a-million.11 Using such a linear relationship between dose and
response: (1) assumes that any level of exposure will increase cancer risk; (2) drives
PHGs to near zero levels (low parts per trillion in this case); and (3) precludes the
assessor from evaluating whether a threshold dose exists below which there is no
increased risk of cancer. In this regard, small intestinal tumors in mice were not
observed below drinking water concentrations of 30,000 or 60,000 ppb, depending on
the choice of control group.
Two separate panels of experts reviewed the 2009 draft PHG, the first of which
reviewed a pre-release version of the proposed PHG. One of the reviewers in the first

7 http://www.cdph.ca.gov/certlic/drinkingwater/Pages/Chromium6sampling.aspx
8 Id.
9 http://www.atsdr.cdc.gov/toxprofiles/tp.asp?id=62&tid=17
10 http://oehha.ca.gov/water/phg/chr6draft082009.html
11 US EPA Guidelines for Carcinogen Risk Assessment (2005), available at
http://www.epa.gov/cancerguidelines/
CMTA/ACC Comments to DPH-11-005
Attachment 1
Page 10

panel was critical of OEHHA’s assessment for failing to consider whether a threshold
dose exists for Cr6 toxicity via ingestion.12 A reviewer on the second external peer
review panel criticized OEHHA’s assumption “that Cr (VI) in drinking water has a
mutagenic MOA with no threshold,” and noted that the assumption resulted in an
“unrealistically low” PHG of 0.06 ppb.13 These views were consistent with the majority
findings of a nine member expert peer review panel convened to review a similar draft
assessment of Cr6 prepared by US EPA (see below).
Despite the peer reviewers’ criticisms, OEHHA revised the proposed PHG downward in
December, 2010, to 0.02 ppb after applying “age dependent adjustment factors.” It then
formally adopted the 0.02 ppb PHG in July, 2011.14
Cr6 MOA Research Project
The Cancer Guidelines emphasize the necessity of understanding of biological activity
to conduct a credible cancer dose-response assessment. The Cancer Guidelines
indicate that the mechanism need only be partially known and distinguishes between
“mechanism of action” and “MOA”; understanding MOA requires less information than
knowing the complete mechanism. Developing information about a carcinogenic MOA
requires identification of biological changes necessary for tumor development; these
changes are called “key events.” Almost no MOA information was developed in the
NTP Study.
Hence, in 2009, after publication of the NTP Study, a dozen research organizations,
under the project management of ToxStrategies (a nationally recognized environmental
health research and scientific consulting firm funded by ACC), conducted extensive
peer-reviewed research designed to elucidate the MOA for the development of small
intestinal tumors in mice. These MOA studies used advanced scientific approaches and
followed the recommendations in the Cancer Guidelines.
The MOA Studies were designed to: (1) determine why the tumors occurred in the NTP
Study (i.e., the MOA that produced the tumors); (2) expand the NTP Study findings to
evaluate early key events at lower doses; and (3) develop information on the differences
between rodents and humans with regard to the biological kinetics of ingested Cr6.
US EPA External Peer Review Panel
In September, 2010, US EPA issued a draft Toxicological Review of exposure to Cr6 in
drinking water under its Integrated Risk Information System (IRIS) program. US EPA
derived a cancer slope factor from the same NTP study that OEHHA used to support its

12 http://oehha.ca.gov/water/phg/pdf/Cr_BJeldanes090909.pdf
13 http://oehha.ca.gov/water/phg/pdf/092010RossmanReview.pdf at page 4.
14 http://oehha.ca.gov/water/phg/072911Cr6PHG.html