{"id":351,"date":"2010-01-12T16:53:59","date_gmt":"2010-01-12T21:53:59","guid":{"rendered":"http:\/\/blogs.edf.org\/nanotechnology\/?p=351"},"modified":"2026-04-02T11:06:52","modified_gmt":"2026-04-02T16:06:52","slug":"wont-we-ever-stop-playing-whack-a-mole-with-regrettable-chemical-substitutions","status":"publish","type":"post","link":"https:\/\/blogs.edf.org\/health\/2010\/01\/12\/wont-we-ever-stop-playing-whack-a-mole-with-regrettable-chemical-substitutions\/","title":{"rendered":"Won\u2019t we ever stop playing whack-a-mole with \u201cregrettable chemical substitutions\u201d?"},"content":{"rendered":"

Richard Denison, Ph.D., is a Senior Scientist.<\/em><\/p>\n

In recent days, two compelling cases have surfaced of so-called \u201cregrettable substitutions\u201d \u2013 industry responding to concerns about the use of one dangerous chemical by replacing it with another that is less well-studied, or at least not currently in the crosshairs.<\/p>\n

Case 1<\/strong>:\u00a0 Chinese manufacturers of children\u2019s jewelry, responding to concerns and restrictions on the use of lead in such products<\/a> produced for export to the U.S., have replaced it with cadmium<\/a>, a known human carcinogen and developmental toxicant that, if anything is even more toxic to kids than lead \u2013 but is not subject to any restrictions in such kids\u2019 products.<\/p>\n

Case 2<\/strong>:\u00a0 American food product manufacturers, responding to concerns about the devastating effects on the lungs of workers exposed to diacetyl \u2013 an artificial butter flavoring used in many products, most notably microwave popcorn \u2013 have begun to replace it with closely related chemicals<\/a> likely to break down into diacetyl or otherwise have similar effects.<\/p>\n

Are we destined forever to play this dangerous variant on the game of whack-a-mole, or can something be done?<\/p>\n

Investigative journalism to the rescue<\/em><\/strong><\/p>\n

An interesting side-note to both cases:\u00a0 Journalists<\/em><\/strong> have played the major role in exposing these debacles.<\/p>\n

In case 1, it was not our government, but rather Justin Pritchard at the Associated Press<\/a>, that brought the lead-to-cadmium bait-and-switch to light.\u00a0 AP commissioned its own product testing, testing 103 items \u2013 charm bracelets, pendants and the like — bought in New York, Ohio, Texas and California in November or December 2009.\u00a0 It found that 12 percent of the items contained at least 10 percent cadmium, with the highest containing 91 percent!<\/p>\n

In case 2, while the National Institute for Occupational Health and Safety (NIOSH) has been hot on the trail<\/a> of diacetyl and substitutes, it was Andrew Schneider<\/a>, a longtime investigative reporter writing for the AOL news outlet Sphere<\/em><\/strong>, who has most recently publicized the quiet replacement of diacetyl with closely related chemicals<\/a>.\u00a0 [Note added 1\/13:\u00a0 I was remiss in not realizing and noting the extensive coverage of this issue going back many months that has been going on at The Pump Handle blog<\/a>.]<\/em><\/p>\n

Isn\u2019t it obvious that such substitutions should be avoided?<\/em><\/strong><\/p>\n

One might think that the chemicals considered as substitutes for a known danger would get scrutinized a little more closely than usual, in order to avoid repeating unwanted history.\u00a0 But a combination of incomplete or inadequate regulations, resource-strapped government agencies and entrenched political resistance to market intervention work to perpetuate a lethally flawed system of chemicals management in this country.<\/p>\n

From a scientific standpoint, avoiding the use of any toxic metal in making kids\u2019 products would seem to be a no-brainer.\u00a0 The AP story points out that virtually nontoxic zinc is a suitable substitute metal for use in children\u2019s jewelry.\u00a0 But this case apparently was driven down the path of least resistance:\u00a0 Cadmium has been used domestically in China for kids\u2019 jewelry and related products for many years, which likely explains the rapid transition to using it for exports in the face of newly-enacted U.S. restrictions on lead.<\/p>\n

The diacetyl case is equally hard to fathom from a purely logical \u2013 dare I say na\u00efve? \u2013 standpoint.<\/p>\n

Inhalation of diacetyl leads to a wholly debilitative lung condition whose name speaks for itself: obliterative bronchiolitis<\/a><\/em><\/strong>.\u00a0 Previously known to affect workers exposed to certain types of fumes in heavy industry, its association with diacetyl in butter flavorings began to be recognized only in 2000, when the first cases of what is now known as \u201cpopcorn workers lung\u201d were identified at a microwave popcorn plant in Missouri.<\/p>\n

First thought to be confined to industrial workers (albeit in the food industry), cases of this disease traced to diacetyl exposure have now been found in service industry workers and even in an individual consumer<\/a> who reportedly ate two bags of microwave popcorn a day and enjoyed inhaling their aroma (who doesn\u2019t?).<\/p>\n

Andrew Schneider reports<\/a> on the case of a Blockbuster Video employee who contracted the condition after microwaving many bags of popcorn on a nightly basis to fill the old-fashioned popcorn machine in the store.\u00a0 She is the third known case among of non-factory workers.<\/p>\n

In response to the horrible publicity surrounding diacetyl, a number of major food companies \u2013 General Mills and ConAgra (owner of Orville Redenbacher\u2019s) among them \u2013 announced they would no longer use it.<\/p>\n

So what have they moved to instead?\u00a0 As noted by Andrew Schneider, some companies have shifted to \u201cnatural materials\u201d known variously as starter distillates and diacetyl trimmers.\u00a0 [Note added 1\/13:\u00a0 An astute reader has <\/em>posted a comment<\/em><\/a> noting that the reference in the original\u00a0Sphere <\/strong>article to “diacetyl trimmer” is likely a typo, and should actually be “diacetyl <\/em>trimer<\/strong>.”\u00a0 <\/em>This chemical<\/em><\/a> is essentially comprised of three linked diacetyl molecules.\u00a0\u00a0 Indeed, <\/em>meeting notes <\/em><\/a>posted on the website of the Division of Occupational Safety and Health of the California Department of Industrial Relations cite John Hallagan, general counsel for the Flavor and Extract Manufacturers Association, indicating that a trimer of diacetyl is one substitute for diacetyl now being used.]<\/em><\/p>\n

Schneider notes that these \u201csubstitutes\u201d either contain diacetyl or release it upon contact with heat and moisture (gee, how likely is that to happen?).\u00a0 He cites NIOSH physicians who describe these materials as not representing any real substitution at all.\u00a0 He also cites a trade association representative saying this shift is occurring so that companies can label their newly-formulated products as \u201cnatural.\u201d\u00a0 [Note added 1\/13:\u00a0 Thanks to <\/em>another very interesting post<\/em><\/a> from last week on this subject of diacetyl substitutes by Celeste Monforton at The Pump Handle, I have learned that NIOSH and OSHA have\u00a0both stated in writing their concern about the lack of safety data on substitutes and the concern that they break down into diacetyl.\u00a0 NIOSH did so in a <\/em>recent letter <\/em><\/a>sent to new OSHA Administrator David Michaels.\u00a0 OSHA did so in a January 2009 <\/em>Federal Register notice<\/em><\/a>, stating:\u00a0 “Both diacetyl trimer and the sulfite adduct of diacetyl have a low vapor pressure in their basic form, and are thus less likely to evaporate and result in employee inhalation exposures during the production process. However, both are converted to diacetyl during consumer food preparation, so that the foods when consumed will contain diacetyl. For example, if placed on popcorn, both convert to diacetyl when the popcorn is popped.”]<\/em><\/p>\n

To describe another substitute, I need to provide a short chemistry lesson.\u00a0 Diacetyl is a nickname for the chemical, 2,3-butanedione.\u00a0 It looks like this:<\/p>\n

\"2,3-butanedione\"<\/p>\n

Some companies who tout their move away from diacetyl have replaced it with flavorings containing this chemical:<\/p>\n

\"2,3-pentanedione\"<\/p>\n

This chemical is named 2,3-pentanedione.\u00a0 As you can see, even if you\u2019re not a chemist, the only difference is the addition of a single carbon atom, from a total of four (to which the \u201cbuta\u201dprefix refers) to five (to which the \u201cpenta\u201d prefix refers).<\/p>\n

They should know better<\/em><\/strong><\/p>\n

You also don\u2019t have to be a toxicologist to have the following thought pop into your head faster than you could make a bag of microwave popcorn:\u00a0 If these chemicals look so similar, might not they affect people\u2019s lungs in a similar manner?\u00a0 And might not a company want to thoroughly test the second chemical before claiming it to be a safe replacement for diacetyl?<\/p>\n

This past November, NIOSH did an inspection of a General Mills \u201cbakery mix production facility\u201d located in Los Angeles.\u00a0 In the resulting inspection report, termed a Health Hazard Evaluation<\/a>, NIOSH reported that the company had replaced most, but not all, diacetyl-containing flavorings with ones containing 2,3-pentanedione.\u00a0 Detectable levels of this chemical were found in the air in the plant and could be measured especially where workers bagged the powdered bakery mixes.<\/p>\n

NIOSH also reported that a number of plant workers exhibited respiratory symptoms while at work.\u00a0 And lung function tests performed by NIOSH found \u201chigher than expected\u201d evidence and incidence of respiratory problems, compared to the U.S. adult population; for example, 18% of the workers had \u201crestrictive patterns\u201d indicative of possible lung disease.\u00a0 None of the workers exhibited popcorn worker lung-like symptoms, however.<\/p>\n

None of this proves 2,3-pentanedione is risky, of course.\u00a0 But it certainly begs the question.<\/p>\n

Noting in its report that \u201ca \u2018safe\u2019 level of diacetyl has not been established, and even low levels of diacetyl are potentially hazardous,\u201d NIOSH goes on to state:<\/p>\n

The toxicology of diacetyl substitutes is only now being studied. \u00a0Because 2,3-pentanedione, 2,3-hexanedione, and 2,3-heptanedione all share the same functional alpha-diketone group as diacetyl, these compounds may also share diacetyl\u2019s mechanism of toxicity.<\/p>\n

In other words, the operative presumption should be that 2,3-pentanedione and related chemicals affect people the same way diacetyl does.<\/p>\n

Indeed, NIOSH\u2019s report recommends to General Mills that \u201cUntil more is known about 2,3-pentanedione and similar alpha-diketone compounds, do not assume these compounds are safe<\/em><\/strong>.\u201d (emphasis added)<\/p>\n

Yet these chemicals continue to be used as substitutes for diacetyl.<\/p>\n

What can be done to avoid \u201cregrettable substitutions\u201d?<\/em><\/strong><\/p>\n

The two examples above may strike you as no-brainers, but there are many more cases that are not so obvious or where there aren\u2019t such clear red flags.<\/p>\n

I can sympathize with companies caught unawares when a chemical they use crashes onto the radar screen.\u00a0 Nor is it hard for me to imagine they might leap at the first available alternative that is identified, based on nothing more than the fact that it is not, at least technically, the chemical of concern.<\/p>\n

But these impulses can be downright dangerous in the context of our current policy and regulatory climate that has allowed most chemicals in or entering commerce to escape adequate testing or safety assessment.\u00a0 That failing makes it all the more likely that a chemical chosen as a substitute for a known bad actor is either no better or untested and unstudied.<\/p>\n

As readers of this blog know, the poster child for this failed policy is the 1976 Toxic Substances Control Act (TSCA).\u00a0 TSCA \u201cgrandfathered in\u201d the more than 60,000 chemicals on the market at the time, without requiring any testing or demonstration of their safety.\u00a0 Measured by tonnage, the vast majority of chemicals on the market today \u2013 34 years later \u2013 is comprised of those same chemicals.<\/p>\n

What changes to TSCA could lessen the likelihood of further regrettable substitutions?<\/p>\n

Here are a few suggestions, each of which is a featured plank in the platform of the Safer Chemicals, Healthy Families campaign<\/a><\/em><\/strong> with which EDF is closely working.<\/p>\n

1.\u00a0\u00a0\u00a0\u00a0\u00a0 <\/strong>Adopt a comprehensive approach to testing and assessing the safety of chemicals in commerce<\/strong>:<\/p>\n

First, we simply must bite the bullet and start the process of digging ourselves out of the hole created by TSCA.\u00a0 While it will require considerable time and expense, TSCA reform must include a requirement that all chemicals be shown to be safe as a condition to enter or remain on the market, based on robust information developed on the uses, hazards of and exposures to those chemicals.<\/p>\n

Some, especially in the chemical industry, would have us skip this altogether.\u00a0 As I noted in previous posts (here<\/a> and here<\/a>), they suggest we simply identify the usual top suspects, maybe require further testing and study of them, and then maybe even regulate a handful of those \u2013 and be done with it.\u00a0 Their estimates of how many chemicals might \u201crise to the top\u201d range from \u201c50-100<\/a>\u201d (subscription required) to \u201c5%<\/a>\u201d of chemicals in use today.<\/p>\n

As I’ve argued before<\/a>, there’s an inherent contradiction here.\u00a0 The chemical industry is among the first to cry “regrettable substitution” when insufficient attention is given to what will replace a chemical targeted by state or federal authorities for restrictions.\u00a0 But how are we ever to compare alternatives and select safer ones with confidence unless we have good information about them?<\/p>\n

2.\u00a0\u00a0\u00a0\u00a0\u00a0 <\/strong>Maximize public and market availability of chemical information:<\/strong><\/p>\n

Companies and institutions that use chemicals to make products, or that sell, buy or use those products, as well as individual consumers, make decisions involving chemical choices every day.\u00a0 Those choices are often ill-informed today, based on assumption instead of data, or incomplete or biased information.<\/p>\n

Companies need to know what chemicals are in the products they\u2019re making, buying, selling or using, what is known about those chemicals\u2019 hazards, and what the potential alternatives to such chemicals are.\u00a0 They also need to know when government has identified a chemical to be of concern and is considering initiating regulatory action.<\/p>\n

Only by requiring the development and broad sharing of sound and complete information about chemicals can we hope to address what amounts to a major market failure perpetuated by our current chemicals policies.<\/p>\n

3.\u00a0\u00a0\u00a0\u00a0\u00a0 <\/strong>Drive companies as well as government to prioritize efforts to develop, identify and assess the safety of alternatives to chemicals of concern:<\/strong><\/p>\n

Government needs to have the authority to direct both its own resources and attention and those of companies toward developing and identifying safer alternatives to chemicals of concern.\u00a0 Doing so will require that both carrots and sticks are embodied in the range of tools available to government.\u00a0 For example, government needs:<\/p>\n