SUCRALOSE

LIFE AFTERASPARTAMEAspartame should never have reached the marketplace.But even if the authorities were to remove it from saletomorrow, how much faith should consumers place in theother artificial sweeteners on the market? PATTHOMAS REPORTS

If sucralose is sosafe, why doesnnanufacturer

There is not a single artificialsweetener on the markettbat can claim, beyond allreasonable doubt, to be safefor humans to consume.

Saccharin, cyclamate and acesulfame-Khave all been show to cause cancer inanimals. Even the family of relativelybenign sweeteners known as polyols, suchas sorbitol and mannitol, can cause gastricupset if eaten in quantity,

NutraSweetbelieves that its newaspartame-basedsweetener, Neotame,is 'revolutionary'; but,seemingly, it is only amore stable version ofaspartame. This leavesthe market wide openfor sucraiose.

Sucralose, soldcommerciallyas Splenda, wasdiscovered in 1976by researchers working for British sugarrefiner Tate & Lyle. Four years later, Tate& Lyie joined forces with Johnson &Johnson to develop and commercialisesucralose under the auspices of a newcompany, McNeil Specialty Products (nowcalled McNeil Nutritionals). Sucraiosehas been approved by more than 60regulatory bodies throughout the world,and is now in more than 3,000 productsworldwide. In the US, Coca-Cola hasdeveloped a new diet drink sweetenedwith Splenda, and other major soft drinkmanufacturers are expected to follow suit.

such a ferventneed to suppressany criticism of it?

Splenda has had to rethink it's slogan"made from sugar, so it tastes like sugar"in the wake of a heated US legal challengeand a recent ruling by the New ZealandAdvertising Standards Authority tbatsaid it confused and mislead consumers.While it is true that sugar, or sucrose, isone of the starting materials for sucralose,its chemical structure is significantlydifferent from that of sucrose.

In a complex chemical process, thesucrose is processedwith, among otherthings, phosgene(a chemical-warfareagent used duringWWI, now a commonintermediary in theproduction of plastics,pesticides and dyes),and three atoms ofchlorine are selectivelysubstituted for threehydroxyl (hydrogenand oxygen) groups

naturally attached to the sugar molecule.

This process produces l,6-dichloro-l,6-dideoxy-beta-D-fructofuranosyl-4-chloro-4-deoxy-alpha-D-galactopyranoside(also known as trichlorogalactosucroseor sucralose), a new chemical substancewhich Tate & l.yle calls a 'water-solublechlorocarbobydrate'.

Accepting Tate & Lyle's classificationof sucralose as a chlorocarbohydrate atface value raises reasonable concernsabout its suitability as a food additive.Chlorinated carbohydrates belongto a class of chemicals known as

' " - ideal lor the whole family -

chlorocarbons. This class of chemicalsincludes a number of notorious humanand environmental poisons, includingpolychlorinated hiphenyls (PCBs);aliphatic chlorinated carbohydrates;aromatic chlorinated carbohydratessuch as DDT; organochlorine pesticidessuch as aldrin and dieldrin; andaromatic chlorinated ethers such aspolycblorinated dioxins (PCDD) andpolycblorinated dibenzofurans (PCDF).

Most of the synthetic chlorinatedcompounds that we ingest, such as thepesticide residues in our food and water,bio-accumulate slowly in the body; andmany cause developmental problems inthe womb or are carcinogenic. How do weknow that sucralose is any different?

Tate & Lyle insists that sucralosepasses through the body virtually intact,and that the tight molecular bondbetween the chlorine atoms and the sugarmolecule results in a very stable andversatile product that is not metabolisedin the body for calories. This doesn'tmean, however, that sucralose is notmetabolised in the body at all, and critics

050 THE ECOLOGIST SEPTEMBER 2005

SUCRALOSE

like HJ Roberts argue that, duringstorage and in the body, sucralosebreaks down into among other things1,6 dichlorofructose, a chlorinatedcompound that has not been adequatelytested In humans.

Tate ik Lyie maintains that sucraloseand its breakdown products have beenextensively tested and proven safe forhuman consumption. The companynotes that in seeking approval from theUS Food and Drug Administration (FDA),McNeil Specialty Products submittedmore than 110 studies that attested tothe safety of sucralose.

BUT CAN CONSUMERS TRUST THISRESEARCH DATA?The vast majority of studies submitted tothe FDA were unpublished animal andlahoratory studies performed by Tate &Lyle itself, and therefore liable to chargesof potentially unacceptable bias. Onlyfive involved human subjects, and thesewere short-term, often single-dose,studies that clearly could not adequatelyreflect the expected real-world usage ofsucralose. After questions were raised bytbe FDA about tbe safety of sucralose fordiabetics, and prior to approval, a furtherfive human studies were eventuallysubmitted. On 1 April 1998 the FDAapproved sucralose for liTnited uses; oneyear later it approved it as a general-purpose sweetener.

Some questions about sucralose'ssafety, arising from the data submittedto the FDA, remain unanswered. Thesestudies included unsettling findings aboutanimals, which, when exposed to highdoses of sucralose, experienced:

• shrunken thymus and spleen;• enlarged liver and kidneys; and• reduced growth rate in adults andnewborns.

In tbe FDA's 'final-rule' report, severalof the studies submitted by McNeil werefound to have 'inconclusive' resultsor were 'insufficient' to draw firmconclusions from them. These included:• a test tbat examined the clastogenicactivity (ability to break chromosomesapart) of sucralose, and a test that lookedfor chromosomal aberrations in humanlymphocytes exposed to sucralose';

• a series of three animal genotoxicitystudies; and• laboratory studies using lympbomatissue from mice which showed thatsucralose was 'weakly mutagenic' (capableof causing cellular mutations).

Clastogenic, genotoxic and mutagenicsubstances are all potential risk factors inthe development of cancer.

In addition to tbese, three studies thatlooked at very specific 'anti-fertility'effects of sucralose and its breakdownproducts, especially witb regard to spermproduction were also deemed insufficient;this is particularly worrying, since other'cblorosugars', such as 6-chloroglucose,are currently being studied as anti-spermatogenic drugs.

Furthermore, the administrationobserved that McNeil bad failed toexplain satisfactorily a reduction in bodyweight seen in animals fed sucralose andthat 'additional study data were needed toresolve this issue'. Ironically for a productthat 'tastes like sugar', McNeil arguedtbat weight loss was due to tbe 'reducedpalatability of sucralose-containingdiets'. FDA reviewers also found thatat mid to bigh doses there was a trendtowards 'decreasing wbite blood cell andlymphocyte counts with increasing doselevels of sucralose'. This was dismissedas having no 'statistical significance' bythe FDA; in healthy animals and humansthis may be so, but what happens wbenalready immune-compromised individualsingest sucralose?

Tate & Lyle says that any lingeringconcerns about sucralose are unfoundedand tbat only a small amount, 15-20 percent, of sucratose is absorbed and brokendown in the human gut. The rest passesthrough tbe body unmetabolised and isexcreted in urine and faeces. This in itselfprovokes important questions.

• What happens to sucralose that isflushed down the toilet? Does it remainstable or react with other substances (forinstance, the chlorine used in water-treatment plants, or microbial life) toform new compounds?• Is sucralose or any resulting chemicalcompound it may form safe for theenvironment? Is it harmful to aquatic lifeor wild animals?

• Will sucralose begin to appear in ourwater supply, in the way that certaindrugs have, silently increasing ourexposure to it? And would that increasedexposure be safe?

PUBLISH AND BE SUEDIn the face of emerging public criticism,lawyers for Tate & lyle are alreadygearing up for a battle. According toattorney James Turner, a key player inthe aspartame drama, 'there's going to bea huge fight about Splenda in the nextfew months... [Tate & Lyle's] lawyersare already on the case trying to shuteverybody up'.

It's a tactic that worked well forMonsanto, which certainly used legalpressure against anyone who criticisedNutraSweet. Recently, the publisher oftbe local newspaper the Brig!iton Argusconsidered It prudent to publish anapology composed by Tate & Lyle (ortheir lawyers) or face a legal action fordefamation and loss of sales after printingan article suggesting that sucralose washarmful to humans.

Tate & Lyle's first high-profile victim,however, was mercola.com - one oftbe world's most visited internet healthsites. Run by Dr Joseph Mercola, tbesite has been a vocal critic of sucralosefor years. Instead of carrying freelyavailable information on sucralosethat might stimulate spirited publicdebate, it now carries tbe followingmessage: 'Attorneys acting on behalfof the manufacturers of sucralose,Tate & Lyle Pic, based in London,England, bave requested that theinformation contained on this pagenot be made available to internet usersin Fngland.'

At this point, concerned consumersshould be asking themselves severalquestions. Does the story of sucralosesound familiar? If sucraiose is safe beyondany reasonable doubt, why is there such afervent need to suppress any criticismof it? Finally, whom do such tacticsreally serve? Do they serve the consumerand the principles of choice, information,safety and redress? Or do they servethe corporate machine and its needto keep generating profits withouttaking responsibility for the human costof doing so?

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