Contamination Control of Infant Formula

They are arguably the most vulnerable consumers of commercial food products, yet also the least likely to effectively articulate distress caused by contaminated products. Who are they? Newborns and infants – the most fragile customers and the least able to guarantee themselves protection from food-borne illness. And in this new era of a global market with food products or components sourced from a multinational supply chain, it is increasingly difficult to maintain a perimeter of safety around these consumers. But is this a new problem in food safety or are we just seeing an old problem played out on a larger global stage? Read on to learn more.

…in 1980, the Infant Formula Act was signed into law by then President Jimmy Carter.

Although we might like to think that commercial replacements for human breast milk are relatively modern creations, formula actually has a significantly lengthy history. Back as far as the late 1800s, powdered preparations derived from cows’ milk were available to affluent families although, until after the Great Depression, the majority of infants were breastfed through their first year of life. The decline of such traditional feeding – and parallel rise in the use of commercially prepared formula – can be traced to the 1940s and early 1950s when liquid formula became available and was promoted as a modern and convenient alternative to the mother’s milk. By 1958, only 30% of parents reported breastfeeding their babies and by the early 1970s this number had declined again to around 25%. Clearly, the landscape for commercially manufactured products for newborns and infants was looking rosy indeed when, in 1980, the Infant Formula Act was signed into law by then President Jimmy Carter. Forming an amendment to the Federal Food, Drug, and Cosmetic Act of 1938, this update established a raft of minimum standards of nutrition for manufactured infant formula products across all brands, ultimately leading pediatric healthcare professionals to support their use as an alternative to breastfeeding.

None of this is good news for parents.

But of course the picture is rarely as rosy as it first appears and infant formula has not been without its controversies, with tainted products periodically rocking the market. As recently as 2017, an Environmental Defense Fund study, for example, found more than 2000 different products contained detectable levels of lead.(1) Although present at a low threshold, exposure to any level of the neurotoxic element is unacceptable for infants whose brains and nervous systems are still very much in development. And let us not forget that, for children under the age of six years, the acknowledged threshold is just 10mg/deciliter of blood. Exposure to lead – a heavy metal with the chemical symbol Pb (from the Latin plumbum) – beyond these limits potentially leads to damage to the central nervous system, brain, kidneys, and reproductive system, and in the case of high levels of contamination convulsions, coma and death may result. None of this is good news for parents.

But lead is not the only contaminant to be aware of.

Late in 2017, a French manufacturer of infant formula was found responsible for a rash of salmonella outbreaks from a plethora of product brands. Of the 50,000 cases of salmonella poisoning reported in the US annually, around one third of those involve children under the age of four years with the symptoms ranging from headache and fever to nausea, vomiting, abdominal cramps and diarrhea. Equally, in 2016, US baby food brand Sammy’s Milk Baby Food, manufactured by Graceleigh, Inc, headquartered in Newport Beach, CA, was recalled by the federal Food and Drug Administration (FDA) due to a breakdown in testing protocol. Finding that the company had not tested its Sammy’s Milk line for cronobacter, a bacterium that is found not only in ultra-dry food environments such as powdered milk, tea, starches, and infant formula, but also in sewer water, the FDA encouraged the company to issue a voluntary recall. What is the issue with cronobacter? According to the Centers for Disease Control and Prevention (CDC), this bacterium may be responsible for fevers, poor feeding, sepsis, and seizures in babies fed with contaminated powdered formula and, in infants below the age of 2 months, cronobacter may lead to meningitis, resulting in a 40% mortality rate of affected patients.(2)

And Sammy’s Milk Baby Food did not only offer formula with a side of germs. It also offered lead. According to an ABC7.com news article, a lawsuit filed in Orange County, CA, in June of this year cited Graceleigh Inc. as one of two companies whose baby formula products contained unacceptable levels of the neurotoxin. Ceasing trade in the state of California, the company is till under investigation for allowing the release of products containing between 13 and 15 times the maximum allowable dose of lead.(3)

OK, so we have lead – which is toxic but a naturally occurring element – and we have the bacterium cronobacter.

But how does the chemical melamine enter the picture? July of this year marks a decade since the country’s biggest infant formula scandal rocked China when urologist Zhang Wei first treated four pediatric patients with kidney stones. Since kidney stones are rarely found in children – especially in babies – the doctor intuited that the cause must be something common to all of the patients, ultimately tracking it down to commercially manufactured powdered formula. In a scandal that would eventually sicken more than 300,000 babies and kill 6, the Chinese government declared a national food-safety emergency when it was found that melamine had been added to milk in order to boost its protein levels. In the aftermath, one of the companies which supplied the tainted product, Sanlu, was forced into bankruptcy, with its chairwoman given a life sentence for failing to stop the sale of the contaminated product. She fared better than the dairy farmer and local supplier who distributed tainted powder, however – both were executed the following year.(4)

Looking back at the Chinese infant formula scandal it is easy to place the responsibility squarely on the shoulders of corporations like Sanlu whose profit margins demand an ever-increasing turnover. In his 2017 book, On Feeding the Masses: An Anatomy of Regulatory Failure in China, author John Yasuda notes that the increasing prosperity in China has led to an uptick in demand for milk which is not supported by the country’s dairy industry. In an article in Quartz, Yasuda notes: ‘”The government was sort of trying to encourage milk consumption,” […] But most of the large milk conglomerates didn’t have their own pasture lands, so more and more small farmers were roped in as suppliers to large firms, and asked to meet demanding production schedules.’(5) And, as we know, where demand for production exceeds ability to produce shortcuts are inevitably taken leading to problems further down the line. And this is probably why the scandal provoked a decade’s worth of legislative reform in China, as new food safety laws were put into place. As of the beginning of this year, any infant formula product – whether produced domestically or imported – must obtain a registration from the China Food and Drug Administration (CFDA) before it can legally be sold.(6) Interestingly, given the erstwhile bewildering number of competing formula products, each company can now register a maximum of nine formulas within three product series. And each registration may come at a price: on-site inspections of applicants – including foreign manufacturers – at the discretion of the CFDA. We’ll be interested to see how that plays out in the upcoming months.

And besides melamine, cronobacter, and salmonella, there’s now a new problem of contamination in powdered infant formulae – have you ever heard of ‘fried rice syndrome’?

Although it sounds like a joke, ‘fried rice syndrome’ is anything but. In June of this year, it was reported that a Texas diner, Germaine Mobley, filed a $1million suit against a Chinese buffet restaurant after a lunch sent her to hospital, ultimately ending up in the intensive care unit. The culprit in that case was the spores of a bacterium known as Bacillus cereus which is often found in cooked foods that should be hot when ingested but which are improperly maintained at room temperature. Although undetectable by taste, the spores of B cereus, a Gram-positive aerobic (or facultatively anaerobic), rod-shaped bacterium, attack a host in two rather unpleasant ways. Initially the bacterium acts as a potent emetic, producing a heat-stable cerulide that induces vomiting within as few as 30 minutes of exposure. Later, after an incubation period of between 6 and 15 hours, it produces enterotoxins (nonhemolytic enterotoxin, cytotoxin, and hemolysin) which result in diarrhea leading to dehydration and increased frailty in those affected.(7)

And it is interesting to note that, because this bacterium is responsible primarily for cases of simple food poisoning, many underestimate the gravity of its effects. In a paper published by Edward J. Bottone in the Clinical Microbiology Reviews, this ‘volatile human pathogen […has a] stigma as an insignificant contaminant [but has been] incriminated in a multitude of other clinical conditions such as anthrax-like progressive pneumonia, fulminant sepsis, and devastating central nervous system infections, particularly in immunosuppressed individuals, intravenous drug abusers, and neonates.’(8) And neonates in China are especially at risk: when researchers from the Centre for Disease Control and Prevention in the Zhejiang, Gansu, Jilin, and Shanxi provinces collected 6,656 samples of infant formula from ‘retail, wholesale and online outlets in both rural and urban markets in 31 provincial-level administrative units in China’ it was found that almost 8% had been contaminated by B. cereus at up to 10 colony-forming units (CFU) per gram. Horrifyingly, an additional 1.11% of the samples had levels at over 100 CFU/g.(9) So, given its prevalence and volatility, we should focus on B. cereus as a deadly pathogen that must be contained. But how?

So what can we do to control the contamination?

Bacillus cereus is interesting insofar as it is commonly present in environments from soil to egg whites, vegetables to meat, and has the ability to thrive within a broad range of temperatures. It is resistant to chemical treatments, ultraviolet radiation, x-rays and high energy charged ion radiation, and also to wet and dry conditions. And significantly, the pasteurization process that is so effective in killing competing vegetative cells in raw milk renders the environment uniquely suitable for B cereus to thrive.(10) So what can we do to control the contamination? Two words: hurdle technology.

According to a paper by Aswathi Soni et al, ‘Bacillus Spores in the Food Industry: A Review on Resistance and Response to Novel Inactivation Technologies’ published by Wiley Online Library in 2016, hurdle technology is the application to food of one or more nonthermal or mildly thermal technologies. Because food can be adversely affected by the application of high heat, control factors such as UV radiation when combined with high-pressure processing (HPP) and/or pulsed electric field (PEF) techniques are looking increasingly promising as ways to safeguard food products. HPP is used initially to germinate the spores using either moderate high pressure (MHP) or very high pressure (VHP) germination, which is then followed by inactivation of the spores via either thermal energy, ionizing radiation, or PEF. PEF disrupts the cell via the application of controlled voltage and pulse width, causing the membrane to become semipermeable and therefore deactivated. It is best used to process liquid products, making it ideal for milk in the raw form prior to it being rendered as powder for use in formula. As the authors note: ‘Damage caused by short-period pulses can be resealed by bacterial spores over time, thereby retaining their resistance and rendering PEF inefficient in killing them; but if the pulses are imparted for a longer duration, then the damage caused is irreversible.’(11) In other words, consistency in duration is everything.

Although HPP and PEF technologies are increasingly being adopted to safeguard products such as infant formula, inactivating bacteria like Bacillus cereus continues to remain a significant challenge to the global food industry. Our current technologies rely on a one-two punch – reducing the spores’ resistance and then deactivating them as quickly as possible. But because this is not a one-step process, the opportunity exists for short-sighted, profit-driven shortcuts to be taken. As we have seen in countless examples, where profit is placed ahead of public safety, tragedy will likely follow and, when it comes to a product as critical as infant formula where the lives of the most vulnerable among us are at stake, surely we must shore up our regulatory oversight and ensure that anyone doing business within our borders is adhering to the most stringent of manufacturing standards. And we will be most interested to follow this story and see how this situation develops over time.

What are your thoughts? Do you worry about the contamination of infant formula? Do you have any experience of Bacillus cereus? Please leave us a comment…

References:

1. https://www.verywellfamily.com/baby-food-and-baby-formula-recalls-293993
2. https://www.cdc.gov/cronobacter/definition.html
3. https://abc7.com/food/baby-formula-with-elevated-lead-content-results-in-oc-lawsuit/3574903/
4. https://qz.com/1323471/ten-years-after-chinas-melamine-laced-infant-milk-tragedy-deep-distrust-remains/
5. ibid
6. https://www.chinalawinsight.com/2018/01/articles/corporate/new-era-for-infant-formula-in-china/
7. https://onlinelibrary.wiley.com/doi/full/10.1111/1541-4337.12231
8. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2863360/
9. https://www.dairyreporter.com/Article/2018/11/27/Prevalence-of-bacterial-contamination-of-infant-formula-in-China-warrants-further-research
10. https://onlinelibrary.wiley.com/doi/full/10.1111/1541-4337.12231
11. ibid