01st Mar 2010
Sewage sludge contains all sorts of household and industrial toxins which are flushed down the toilet or private and industrial drains. How could this possibly impact the quality of your ‘natural’ pet food?
Just to remind you: the term ‘natural’ isn’t regulated and the best way to actually get a natural pet food when you want one is to buy a certified organic pet food, which among other things, wouldn’t contain sewage sludge-grown crops or animal ingredients. Verification by an independent party, an organic certification agency, is your guarantee that this is the case.
Non-certified organic pet foods contain so-called ‘conventional’ (i.e., non-certified organic) ingredients. Conventional agriculture routinely uses sewage sludge (also called ‘biosolids’) as ‘fertilizer.’ Every year more than half of the roughly 7 million metric tons of the biosolids produced in the United States are applied as fertilizer to farm fields.
The large amount of human waste processed in sewage plants means that sewage sludge contains high concentrations of phosphates and nitrates, which are desirable components of fertilizers. However, this sludge also contains highly toxic materials such as fluorides, industrial solvents, heavy metals, hormones, antibiotics, and even radioactive waste which may accumulate in the plants that are grown on sludge-fertilized farmland, as well as in the animals that are fed sludge-treated crops.
WHAT TOXINS ARE CONTAINED IN SEWAGE SLUDGE?
Here are just some of the many toxins that were detected by the EPA in sewage sludge from 74 randomly selected publicly owned water treatment/sewage sludge plants in 35 states (Targeted National Sewage Sludge Survey Report, 2009).
For understandable reasons, the EPA study had to limit the analysis to relatively few toxins; it is likely that sewage sludge contains many more toxins that have not been included in the EPA study.
‘Class B biosolids,’ which are the principal type of biosolids applied to land, also contain a variety of enteric pathogens (e.g., E.coli, salmonella). These were also not included in the recent EPA study.
At the end of this page you can find information on some of these toxins (marked in the text with numbers in parenthesis) and the health problems with which they are known to be associated.
Twenty seven of the 28 metals analyzed were found in every sewage sludge sample. The most prevalent were barium(1), beryllium(2), manganese(3), molybdenum(4), and silver(5). The other metals included: aluminum, antimony, arsenic, boron, cadmium, cobalt, lead, mercury, selenium, thallium, tin, vanadium, yttrium, and zinc.
Remember that elemental metals often are very toxic while they are life-sustaining in the forms in which they occur naturally in foods.
Of the six organics analyzed, four were found in at least 72 samples, one was found in 63 samples, and one was found in 39 samples. The most prevalent ‘organics’ are: pyrene(1), fluoranthene(2), 4-Chloroaniline(3).
3. Polybrominated diphenylethers (PBDEs)
PBDEs are a particular class of flame retardant chemicals used in plastics, foams, fabrics and other materials. All 7 of the flame retardants studied except one (BDE-138) were essentially found in every sample; BDE-138 was found in 54 out of 84 samples.
Of the 72 pharmaceuticals analyzed, three (i.e., ciprofloxacin, diphenhydramine, and triclocarban) were found in all 84 samples and nine were found in at least 80 of the samples. However, 15 pharmaceuticals were not found in any sample and 29 were found in fewer than three samples.
Among the detected pharmaceuticals are antibiotics, antibiotic derivatives, and disinfectants: azithromycin(1), ciprofloxacin(2), doxycyclin(3), erythromycin-4(4), tetracycline(5), 4-epipetracycline(6), miconazole(7), ofloxacin(8), trilocarban(9), triclosan(10), the antihistamine medicine diphenhydramine(11), anticonvulsant, mood stabilizing drugs or antidepressants: fluoxetine(12), carbamazepine(13), and the heart burn medicine cimetidine(14).
5. Steroids and hormones
Of the 25 steroids and hormones that were analyzed, three steroids (i.e., campesterol, cholestanol, and coprostanol) were found in all 84 samples and six steroids were found in at least 80 of the samples. One hormone (i.e., 17-a-ethynyl estradiol) was not found in any sample and five hormones were found in fewer than six samples.
Detected were widely used phytosterols (1): Beta Stigmastanol, Campesterol, and Stigmasterol, Cholesterol (2), markers of human fecal matter contamination: the cholesterol derivatives coprostanol and epicoprostanol (a coprostanol isomer formed during treatment of wastewater ), hormones with androgenic activities: testosterone, androsterone, androstenedione (a direct precursor to testosterone), estrogenic hormones natural and synthetic estrogens: estriol, estrone,17-α-estradiol, 17-β-estradiol, β-estradiol-3-benzoate, 17-α-ethynyl estradiol(3*), equine estrogens (‘Premarin’): 17α-dihydroequilin, equilenin, equilin, progestins: norethindrone and norgestrel(4), progestogens: progesterone(5).
This necessarily restricted EPA analysis of toxins contained in sewage sludge shows that a number of known toxins are present in the ‘biosolids’ used in conventional agriculture. Among these are a veritable cornucopia of antibiotics, hormones, and toxic metals, many of which have the ability to accumulate in plants, animals, and humans.
Any ‘natural pet food claim’ that isn’t associated with certified organic pet foods, can therefore not withstand real life scrutiny. These natural pet food claims are often associated with ‘free of hormones’ and ‘free of antibiotics’ statements. The results of this EPA study demonstrate clearly that these natural claims are largely meaningless.
Certified organic pet foods simply cannot contain ingredients that were grown with hormones or antibiotics, whether they are applied intentionally or indirectly through the use of sewage sludge as a fertilizer. Therefore, only certified organic pet foods can, in good conscience and backed by solid science, be considered as natural pet foods.
(1) Kidney disease, cancer, increased mortality, decreased birth weight, hypokalemia – tachycardia, hyper- or hypotension, muscle weakness, paralysis.
(2) Sensitization, pulmonary disease.
(3) Neurotoxicity with symptoms similar to those of Parkinson’s disease.
(4) Gout, copper deficiency anemia, anorexia, profound diarrhea, joint abnormalities, osteoporosis, hair discoloration, reduced sexual activity and death, genotoxicity.
(5) Corrosive damage of the gastrointestinal tract, abdominal pain, diarrhea, vomiting, shock, convulsions, and death; respiratory irritation, irritation to the skin, mucous membranes, and eyes; argyria; thickening of the basement membranes of the renal glomeruli, growth depression, shortened lifespan; hypoactivity; affects the nervous system, leading to weakness, rigidity of legs, loss of voluntary movement, and respiratory paralysis in rats, dogs, and guinea pigs.
1) Recognized as one of the most hazardous compounds to the ecosystem and human health. A confirmed carcinogen that is suspected to be a developmental, endocrine, gastrointestinal, liver, immune system, respiratory, and skin and sense organ toxin.
(2) Causes tumors in lab animals; increases pyrene toxicity.
(3) Carcinogenic. Very toxic if inhaled, swallowed or absorbed through the skin. Causes kidney disease, reproductive, and developmental problems in animals.
PBDEs persist in the environment and accumulate in living organisms. Toxicological testing indicates these chemicals may cause liver toxicity, thyroid toxicity and neuro-developmental toxicity. Ref.
(1) ‘Zithromax’. Skin irritation, eye irritation, conjunctivitis, respiratory tract irritation, gastrointestinal tract irritation with abdominal pain, diarrhea, loose stools, dyspepsia, flatulence, nausea, constipation, taste perversion, anorexia, oral moniliasis, mucositis, vomiting; behavior/central nervous system: ataxia, dizziness, vertigo, agitation, tiredness, nervousness, insomnia; urinary system/kidneys: dark urine caused by hematuria; acute failure, nephritis; blood: leukopenpia, neutropenia, decreased platelet count; cardiovascular system: palpitations, chest pain. Other symptoms may include vaginitis, urticaria, pruritus. Ref.
(2) ’Cipro, …’ Fluoroquinolone toxicity. Including: peripheral neuropathy (nerve damage), tendon damage, heart problems, pseudomembranous colitis, rhabdomyolysis (muscle wasting), toxic epidermal necrolysis, Stevens-Johnson syndrome (cell death causes the epidermis to separate from the dermis); spontaneous tendon rupture and tendonitis; liver failure or serious liver injury (hepatitis); severe central nervous system disorders; Clostridium difficile-associated disease; renal damage and deaths; neurotoxicity in both humans and animals, and photosensitivity or phototoxicity reactions.
(3) ‘Vibramycin,…’ Photosensitive allergic reactions, stomach or bowel upsets, allergic reactions, severe headache and vision problems.
(4) Hives; difficulty breathing, swelling of face, lips, tongue, or throat; chest pain, uneven heartbeats, dizziness, headache, feeling tired or light-headed, fainting; nausea, stomach pain, low fever, lost appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes); watery or bloody diarrhea; vaginal itching or discharge; mild itching or skin rash.
(5) Photosensitive allergic reaction; stomach or bowel upsets; sometimes allergic reactions; very rarely, severe headache and vision problems that may be signs of dangerous secondary intracranial hypertension.
(6) Allergies, renal toxicity, depression, anorexia, salivation, muscle spasms, and dyspnea.
(7) Effects on tumors and cancers has not been studied. Several drug interactions after gastrointestinal absorption. Tachycardia and arrhythmias, aggregation of erythrocytes, anaemia, thrombocytosis, anorexia, nausea, vomiting, diarrhea, irritation, vulvovaginal burning, itching or irritation pelvic cramps, skin rash, cutaneous pruritus, flushes, drowsiness, febrile reactions, hyponatraemia, acute psychosis, arthralgia, anaphylaxis, irritation of the meninges (Reynolds, 1989, Physician’s Desk Reference, 1989). Ref.
(8) Polyneuropathy, convulsions, changes in heart rhythm, rupture of tendons, disturbances of blood glucose metabolism (hyper- and hypoglycemia), hepatitis, swelling, rashes and other dermatological reactions Ref. In animals, salivation, dirty hair coats, soft stools, and decreases of body weight and food intake, decreased body weight and retardation of ossification in fetuses, increased mortality and skeletal variations Ref.
(9) Endocrine disruptor that enhances the biological activity of endogenous testosterone in rats where it significantly increases gene expression in reproductive organs and substantially increases the weight of accessory sexual organs such as the prostate Ref.
(10) Antimicrobial used in many cosmetic and household items; it is suspected to cause bacterial resistance. With chlorine it water, it forms the suspected carcinogen chloroform. With free chlorine in water and upon exposure to UV radiation, it generates intermediates that convert into dioxins which can bioaccumulate. Triclosan acts as an endocrine disruptor in the North American bullfrog Ref. It blocks the thyroid hormone metabolism and significantly impacts thyroid hormone concentrations in rats Ref.
(11) ‘Benadryl, Dimedrol, Nytol, Unisom, Tylenol PM, and Advil PM’. Can cause profound drowsiness; motor impairment (ataxia), dry mouth and throat, flushed skin, rapid or irregular heartbeat (tachycardia), blurred vision, abnormal sensitivity to bright light, pupil dilation, urinary retention, constipation, difficulty concentrating, short-term memory loss, visual disturbances, hallucinations, irregular breathing, dizziness, irritability, itchy skin which may include allergic reactions with outbreak of hives, confusion, decreased body temperature, erectile dysfunction, excitability, and delirium.
(12) ‘Prozac’. Can cause headache, insomnia, nausea, and nervousness, tremors, restlessness, sweating, rash, dry mouth, anxiety, drowsiness, and diarrhea (Messiha, 1993). In animals, it can cause lethargy and affect development Ref, cause lethal seizures Ref. Prozac bioaccumulates in animals Ref. Early postnatal exposure causes adult mice to exhibit depressive and anxious behaviors Ref.
(13) ‘Tegretol,…’. Can cause serious skin reactions with rash/blisters/peeling, itching, or swelling. Can depress bone marrow function (aplastic anemia) with signs of infection (e.g., fever, persistent sore throat), unusual weakness or fatigue, or easy bleeding/bruising Ref. Carbamazepine toxicity has cardiac, respiratory, and neurologic effects Ref and can cause pancreatitis.
(14) ‘Tagamet,…’. Interferes with other drugs and normal metabolism, such as estrogen metabolism (it enhances estrogen activity). It can also affect the central nervous system.
5. Steroids and Hormones
(1, 2) Pytosterols, which are used as anticholesteremic agents, and cholesterol bioaccumulate (in the adrenal glands, ovaries and intestines of rats Ref.
Oxidized cholesterol, β-sitosterol, and campesterol are cytotoxic causing LDL leakage, cell death, and mitochondria dehydrogenase activity Ref, Ref.
(3) A derivative of estradiol. Ethinyl estradiol is an orally bio-active estrogen used in almost all modern formulations of combined oral contraceptive pills (the ‘Pill’). This is the one of 25 steroids or hormones that was not found in the EPA study!
(4) Synthetic progestins used in oral contraceptives.
(5) Natural or synthetic progestogens.