What’s lurking in your cat’s food? A new investigation finds toxic chemicals

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Nearly all tested cat foods contain toxic plastic contaminants , the herbicide glyphosate and heavy metals such as lead, mercury and arsenic, according to a new investigation provided exclusively to CNN.

“Most cats eat the same foods nearly every day, with little variation,” said report author Molly Hamilton, executive director of the Clean Label Project, a Colorado nonprofit that tests consumer products for contaminants and certifies those meeting its standards .

“The contaminants are an ongoing exposure that may accumulate in cats’ bodies over their lifetimes,” Hamilton said. “For example, chronic kidney disease is among the most common causes of death in older cats — the kidneys play a major role in filtering heavy metals.”

Toxins were found in all types of cat food — wet, dry and air- or freeze-dried — even in products labeled as natural and nutritionally superior, according to the analysis released Friday.

“Cat owners increasingly choose premium meats, organic vegetables and cleaner labels, assuming higher prices and quality ingredients mean healthier food,” Hamilton told CNN. “That’s not necessarily the case.”

Clean Label published a similar assessment of dog food in February that found three to 13 times more heavy metals than human food. Lead and cadmium exposure has been linked to canine cancer, a leading cause of death in dogs.

Heavy metals occur naturally in soil, water and air, but agricultural, industrial and mining pollution can increase and spread contamination. Plastics and other contaminants may also enter food during manufacturing, the report said.

“Overall, this appears to be a reasonably conducted analysis,” said Ryan Babadi, science director for Toxic Free Future, a nonprofit consumer product safety organization.

“Major retailers have the responsibility to require their suppliers to eliminate harmful chemicals from pet food and packaging — chemicals that are already being phased out or banned in many other products,” said Babadi, who was not involved in the investigation.

The Pet Food Institute, which represents manufacturers of cat foods, told CNN in an email that pet food manufacturers do implement comprehensive food safety and quality assurance programs.

Those include “ingredient specifications, supplier verification, testing protocols, traceability systems, and science-based preventive controls designed to ensure products are safe, nutritious, and consistent,” said Elise Fennig, the CEO for the Pet Food Institute.

“Cat owners should feel confident that the food they feed their pets is safe and produced according to rigorous regulatory and quality standards.”

The investigation tested 100 top-selling cat foods for more than 122 contaminants, including lead, arsenic , cadmium, mercury, pesticides, herbicides and phthalates, the plastic chemicals linked to an increased risk of death in humans.

Lead was found in 99%, cadmium in 96% and arsenic in 94% of cat food samples across 62 brands. Contamination varied by product type — wet, dry, and air- or freeze-dried — and the type of protein, such as poultry, beef or fish.

Cadmium is classified as a human carcinogen and harms the kidneys and bones. A buildup of lead in the body damages nearly every major organ system. Inorganic arsenic — the type found in soil and water — is also a known human carcinogen .

Dry cat food contained roughly three times more lead than wet or air-dried products. No level of lead is safe for people, and children are most vulnerable: Their bodies absorb up to 50% of ingested lead , compared with about 10% for adults, which can cause stunted growth, decreased IQ, hyperactivity and irritability.

Cats and other small pets also absorb more than larger ones, yet few regulations control contaminants in pet food, Hamilton said. “The absence of safety standards does not mean a contaminant is safe. Most guidelines are designed for farm animals, not kittens or 15-year-old housecats.”

Fish and seafood — popular proteins for cats — had the strongest association with mercury and cadmium, the report found. Because microorganisms in water turn regular mercury into methylmercury, a toxic chemical form that binds tightly to fish tissue, the heavy metal accumulates to higher levels in aquatic animals.

Mercury is toxic to the nervous, digestive and immune systems, as well as the kidneys, lungs and skin, according to the World Health Organization .

Mercury levels were about 18 times higher and cadmium levels about 2.5 times higher in fish- or seafood-based cat foods than in foods made with other proteins. Wet versions of seafood products contained the most mercury — nearly 28 times as much as wet foods made with other meats, especially poultry.

“As the main protein, chicken was better when it came to mercury and cadmium, but we saw higher rates of lead and herbicides in chicken,” Hamilton said. “It’s a whack-a-mole situation — which contaminant do you want to whack?

“That doesn’t mean all fish options were high in mercury — levels depend on manufacturers’ quality-control testing,” she added. “We certified several fish-based foods.”

Nearly 85% of poultry-based foods met Clean Label Project’s purity standard compared with 25.7% of fish and seafood products.

“Every product in this study was purchased at retail, and no brand had any role in selecting products, conducting testing or analyzing the results. No brand saw the results before publication,” Hamilton said.

Although cats are carnivores, many manufacturers add produce to cat food for its antioxidants, minerals and vitamins. Unless grown organically, those plants may be exposed to pesticides. A national report found the vast majority of 100 popular fruits and vegetables tested positive for a wide variety of bug-killers.

The Clean Label investigation tested for glyphosate, which is agriculture’s most widely used herbicide. Glyphosate was found at detectable levels in 37% of products, and cat food with more plants in the first 10 ingredients had higher glyphosate levels.

The WHO’s International Agency for Research on Cancer classified glyphosate in 2015 as “probably carcinogenic to humans.” The US Environmental Protection Agency disagrees.

“On average, cat food with two plant ingredients among the top 10 on the label had roughly 40% more glyphosate than a similar food with one plant ingredient. Cat food with five plant ingredients had nearly four times as much,” Hamilton said.

Another “very concerning finding” was the widespread presence of di(2-ethylhexyl) phthalate, or DEHP, a chemical used in PVC plastics and some food-contact materials that is linked to cancer, birth defects and other health concerns, Babadi said.

“It was detected in about half of the products tested, with the highest levels in canned and pouch products. DEHP contamination could potentially occur during food processing, including through contact with PVC tubing or other farm or food processing equipment,” he said.

“It is encouraging to see those harmful bisphenols, including BPA, were found less frequently, suggesting pet food can be produced and packaged without these endocrine disrupting chemicals,” Badadi added.

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The research did have limitations. Each product was tested from a single batch. Therefore the study could not capture differences that might occur between batches of the same product.

“Brands that routinely screen for contaminants of concern tend to have more consistent results over time,” Hamilton said. “In addition, this study compares contaminant levels across products in each category of wet, dry and air- or freeze-dried. It does not determine whether a specific product will cause harm to a cat.”

If your cat favors seafood, vary its diet with chicken or other proteins to limit daily exposure to mercury and cadmium. Read the ingredient list carefully, however, as cat foods without fish in their name may still contain seafood ingredients and thus higher levels of mercury and cadmium.

According to the Clean Label report, wet or air-dried products are preferable to dry food for lower lead exposure, while avoiding foods with plants in the top 10 ingredients may lower pesticide exposure.

In addition, don’t rely on the first listed ingredient to gauge toxins. In more than a third of tested products, it didn’t tell the full story, Hamilton said.

“The first ingredient on a food label is often the biggest selling point because ingredients are listed by weight,” she said. “We tested and found the first ingredient is not always a reliable indicator of what the food contains, nor does it predict which contaminant may be present at the highest levels.”

One reason: Manufacturers need not disclose which part of a fish or other protein they use, Hamilton said. Wild salmon, for example, may sound healthier, but its liver, kidneys, intestines, head and skin store more chemical pollutants than the rest of the fish.

“Yet you have no idea what part of the fish is in that cat food,” Hamilton said. “The best way to know what’s in your cat’s food is to contact the manufacturer and determine if they test the food – and how frequently they test.

“Because even if they were to tell you what part of the fish that they’re using, without testing, there’s no way to know how free of contaminants it really is.”

It’s also a good idea for consumers to reach out to the company making their cat’s favorite food brand and inquire about testing and quality control standards, experts say.

“Pet owners should take action and urge brands and retailers to ensure toxic chemicals and plastics are not hiding in cat food and its packaging,” Babadi said. “Pets, as part of our families, deserve food that is safe from toxic chemicals.”

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据 CNN 独家获得的一项最新调查显示，几乎所有受测猫粮都含有有毒塑料污染物、除草剂草甘膦以及铅、汞、砷等重金属。

“大多数猫几乎每天都吃同样的食物，变化不大，”报告作者莫莉·汉密尔顿说道。她是科罗拉多州非营利组织“清洁标签项目”的执行董事，该项目负责检测消费品中的污染物，并对符合其标准的产品进行认证。

汉密尔顿说：“这些污染物会持续不断地在猫体内积累，伴随猫的一生。例如，慢性肾病是老年猫最常见的死因之一——肾脏在过滤重金属方面起着重要作用。”

根据周五发布的分析报告，所有类型的猫粮——湿粮、干粮以及风干或冻干的猫粮——甚至包括标榜天然和营养丰富的猫粮产品中都发现了毒素。

汉密尔顿告诉CNN：“猫主人越来越倾向于选择高档肉类、有机蔬菜和成分更清晰的猫粮，他们认为更高的价格和更优质的原料意味着更健康的食物。但事实并非总是如此。”

Clean Label在2月份发布了一项类似的狗粮评估报告，发现狗粮中重金属含量是人类食品的3到13倍。铅和镉暴露与犬类癌症有关，而犬类癌症是导致犬类死亡的主要原因之一。

报告指出，重金属天然存在于土壤、水和空气中，但农业、工业和采矿污染会加剧并扩散污染。塑料和其他污染物也可能在食品生产过程中进入食品。

“总的来说，这似乎是一项进行得相当合理的分析，”非营利性消费品安全组织“无毒未来”的科学主管瑞安·巴巴迪说。

“大型零售商有责任要求其供应商消除宠物食品和包装中的有害化学物质——这些化学物质已经在许多其他产品中被逐步淘汰或禁用，”巴巴迪说道，他并未参与此次调查。

代表猫粮生产商的宠物食品协会在一封电子邮件中告诉 CNN，宠物食品生产商确实实施了全面的食品安全和质量保证计划。

宠物食品协会首席执行官伊莉丝·芬尼格表示，这些措施包括“成分规格、供应商验证、测试规程、可追溯性系统以及旨在确保产品安全、营养和一致的基于科学的预防性控制”。

“猫主人应该确信，他们喂养宠物的食物是安全的，并且是按照严格的监管和质量标准生产的。”

该调查检测了 100 种最畅销的猫粮，检测了 122 种以上的污染物，包括铅、砷、镉、汞、杀虫剂、除草剂和邻苯二甲酸酯（一种与人类死亡风险增加有关的塑料化学物质）。

在62个品牌的猫粮样本中，99%的样本检测出铅，96%的样本检测出镉，94%的样本检测出砷。污染程度因产品类型（湿粮、干粮、风干粮或冻干粮）和蛋白质类型（如禽肉、牛肉或鱼肉）而异。

镉被列为人类致癌物，会损害肾脏和骨骼。铅在体内积聚几乎会损害所有主要器官系统。无机砷——存在于土壤和水中的那种砷——也是一种已知的人类致癌物。

干猫粮的含铅量大约是湿猫粮或风干猫粮的三倍。任何剂量的铅对人体都是不安全的，儿童尤其容易受到伤害：儿童体内可吸收高达50%的摄入铅，而成人吸收率约为10%，这会导致发育迟缓、智商下降、多动和易怒。

汉密尔顿说，猫和其他小型宠物比大型宠物更容易吸收有害物质，但很少有法规控制宠物食品中的污染物。“缺乏安全标准并不意味着污染物就是安全的。大多数指导方针都是针对农场动物制定的，而不是针对小猫或15岁的家猫。”

报告发现，鱼类和海鲜——猫咪喜爱的蛋白质来源——与汞和镉的关联性最强。由于水中的微生物会将普通汞转化为甲基汞（一种能与鱼类组织紧密结合的有毒化学物质），因此这种重金属会在水生动物体内积累到较高水平。

世界卫生组织表示，汞对神经系统、消化系统和免疫系统以及肾脏、肺和皮肤都有毒性。

鱼类或海鲜猫粮中的汞含量比以其他蛋白质为原料的猫粮高出约18倍，镉含量高出约2.5倍。湿粮形式的海鲜猫粮汞含量最高，几乎是其他肉类（尤其是禽类）湿粮的28倍。

“作为主要蛋白质来源，鸡肉在汞和镉含量方面表现更好，但我们发现鸡肉中铅和除草剂的含量较高，”汉密尔顿说。“这就像打地鼠游戏——你想先清除哪种污染物呢？”

她补充说：“这并不意味着所有鱼类食品的汞含量都很高——汞含量取决于生产商的质量控制检测。我们已经对几种鱼类食品进行了认证。”

近 85% 的禽肉食品符合清洁标签项目的纯度标准，而鱼类和海鲜产品的这一比例仅为 25.7%。

“这项研究中的所有产品都是从零售渠道购买的，没有任何品牌参与产品选择、测试或结果分析。在结果发表之前，也没有任何品牌看过这些结果，”汉密尔顿说。

虽然猫是肉食动物，但许多生产商会在猫粮中添加蔬果，以补充其中的抗氧化剂、矿物质和维生素。除非是有机种植，否则这些蔬果可能接触过杀虫剂。一份全国性报告发现，在100种常见的果蔬中，绝大多数都检测出含有多种杀虫剂。

“清洁标签”调查检测了草甘膦，草甘膦是农业中最广泛使用的除草剂。结果显示，37%的产品中含有可检出的草甘膦，而且前十种成分中植物成分较多的猫粮，其草甘膦含量也更高。

世界卫生组织国际癌症研究机构于2015年将草甘膦列为“可能对人类致癌”。美国环境保护署对此持不同意见。

“平均而言，标签上排名前十的成分中含有两种植物成分的猫粮，其草甘膦含量比只含有一种植物成分的同类猫粮高出约 40%。含有五种植物成分的猫粮，其草甘膦含量几乎是后者的四倍，”汉密尔顿说。

巴巴迪表示，另一个“非常令人担忧的发现”是邻苯二甲酸二(2-乙基己基)酯（DEHP）的广泛存在。DEHP是一种用于PVC塑料和一些食品接触材料的化学物质，与癌症、出生缺陷和其他健康问题有关。

他说：“在约一半的受检产品中都检测到了这种物质，其中罐装和袋装产品的含量最高。DEHP污染可能在食品加工过程中发生，包括通过与PVC管材或其他农场或食品加工设备接触。”

巴达迪补充说：“令人鼓舞的是，包括双酚A在内的有害双酚的检出频率有所降低，这表明宠物食品可以在不添加这些内分泌干扰化学物质的情况下进行生产和包装。”

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这项研究确实存在局限性。每种产品都只测试了单一批次的产品。因此，该研究无法捕捉到同一产品不同批次之间可能存在的差异。

汉密尔顿表示：“定期筛查有害污染物的品牌往往能取得更稳定的长期效果。此外，这项研究比较了湿粮、干粮以及风干或冻干等各类产品中的污染物含量，但并未判定特定产品是否会对猫造成伤害。”

如果您的猫咪偏爱海鲜，为了减少其每日汞和镉的摄入量，应在猫粮中添加鸡肉或其他蛋白质。不过，请务必仔细阅读成分表，因为即使猫粮名称中不含“鱼”，也可能含有海鲜成分，从而导致汞和镉含量较高。

根据清洁标签报告，湿的或风干的产品比干的食物更可取，以降低铅暴露量；同时，避免食用前 10 个成分中含有植物的食物，可以降低农药暴露量。

此外，不要仅仅依赖成分表中的第一项来判断毒素含量。汉密尔顿表示，在超过三分之一的受测产品中，第一项成分并不能反映全部情况。

“食品标签上的第一个成分往往是最大的卖点，因为成分是按重量排列的，”她说。“我们测试后发现，第一个成分并不总是能可靠地指示食品的成分，也不能预测哪种污染物含量最高。”

汉密尔顿指出，其中一个原因是：制造商无需披露他们使用的是鱼或其他蛋白质的哪个部位。例如，野生鲑鱼听起来可能更健康，但它的肝脏、肾脏、肠道、头部和皮肤比鱼的其他部位储存了更多的化学污染物。

“然而，你根本不知道猫粮里含有鱼的哪个部位，”汉密尔顿说。“了解猫粮成分的最好方法是联系生产商，确定他们是否对猫粮进行检测，以及检测频率如何。”

“因为即使他们告诉你他们使用的是鱼的哪个部位，但如果不进行检测，就无法知道它是否真的不含污染物。”

专家表示，消费者最好联系生产自己猫咪最喜欢的猫粮品牌的公司，询问其测试和质量控制标准。

巴巴迪表示：“宠物主人应该采取行动，敦促品牌商和零售商确保猫粮及其包装中不含有毒化学物质和塑料。宠物作为我们家庭的一份子，理应享用不含有毒化学物质的安全食品。”