Composting does not kill bacteria July 2009
updated August 28, 2009
Photo Courtesy of San Francisco Bay Area Independent Media Center
Composting does not kill all bacteria and other pathogens. EPA research documents that composting causes some
bacteria to survive in a desiccated state. The addition of moisture revives the bacteria. Yet EPA persists in claiming
Class A sludge (aka, biosolids) is free of disease causing organisms. Yet, the fecal coliform test itself is for primarily
thermotolerant E. coil and kelbsiella. What is not discussed is the bacterial endotoxins and dust which can cause
serious illness and death, such as extrinsic allergic alveolitis -- better known as Chronic
Obstructive Pulmonary Disease (COPD)
Sludge experts love to say toxic sludge is not a hazardous waste. However, the term hazardous waste has no direct
meaning in relationship to human health effects. EPA defined a hazardous waste in FR, 43, #243, p. 58953 to include
those pollutants that will leach out of the soil into groundwater at levels 10 times higher than those allowed in the
drinking water standards. Congress defined hazardous waste in the solid waste law to include any material with
infectious characteristics. Sludge is a solid waste disposal operation run by the Office of Water, rather than the Office
of Solid Waste.
OSHA implied it thought sludge/Biosolids was only used as a fuel when it said, "The National Fire Protection
Association (NFPA) forwarded to the Occupational Safety and Health Administration (OSHA) a research paper (1)
which reported on potential hazards involved with processing, conveying and storing of dried biosolids derived fuel
(BDF). BDF is used in a number of industrial applications. The paper indicated that organic dust can be generated
during the storage of BDF. It also asserted that another organic dust similar to biosolids dust was grain dust." (11)
According to the NIOSH, "Chronic Obstructive Pulmonary Disease "(COPD) has become a major public health concern.
In 1995, it ranked as the fourth leading cause of death in the United States, accounting for over
100,000 deaths--nearly twice as many as in 1980 [NCHS 1997]. In 1994, an estimated 16 million individuals in the
United States had the diagnosis of COPD, representing a 60 percent increase since 1982 [ALA 1996]." (1)
"(COPD) includes chronic bronchitis (ICD-9 codes 490-491), emphysema (ICD-9 code 492), bronchiectasis (ICD-9
code 494), and chronic airway obstruction (ICD-9 code 496). These diseases are commonly characterized by
irreversible airflow limitation. Some authorities include asthma (ICD-9 code 493) and hypersensitivity
pneumonitis (ICD-9 code 495)" (1)
"Acute toxic alveolitis, otherwise known as "organic dust toxic syndrome" (ODTS), can accompany brief, occasional
exposures to heavy concentrations of organic dust in agricultural environment. The contents of the dust inhaled can
include fungal spores, bacteria, bacteria spores and endotoxins. Symptoms of illness often become apparent
between 4 and 8 hours after inhalation of heavily concentrated organic dust". (7)
Microbiological Studies of Compost Plant Dust
Staph, gram negative bacteria, gram positive bacteria and fungi was found in all areas. (no coliform?)
EPA and USDA acknowledged liming sludge does not kill salmonella. The original numbers of Salmonella reappear in
about 30 days.
According to microbiologists, some bacteria form an endospore, a cell type developed from the vegetative bacterial cell
through a sequence of morphological changes. Although the vegetative cell of bacteria is usually killed by heat and
disinfectant, the endospore is resistant to agents that kill the vegetative cell (heating, drying, freezing, chemicals, and
radiation). Nester, Roberts, Pearsall and McCarthy (1978) in their text Microbiology point out the threat
that endospores present. They say: Endospores represent the most resistant form of life known; they tolerate
extremes of heat and dryness, the presence of disinfectants, and radiation. Some members of Bacillus and Clostridium
play a role in fixing atmospheric nitrogen and others cause serious infectious diseases. Thermophilic strains of Bacillus
can grow at temperatures above 70 C (158 F) (p. 260)
Factors Affecting Salmonellae Repopulation in Composted Sludges
The repopulation potential and recovery of Salmonella sp. and their close relatives Arizona spp. and Citrobacter spp.
in sewage sludge which had been composted was examined. Salmonellae growth in previously composted sludge
was found to occur in the mesophilic temperature range (20 to 400C), require a moisture content of -20%, and require
a carbon/nitrogen ratio in excess of 15:1.
These results also indicated that some enteric bacteria, upon desiccation, became dormant and in this
state were highly resistant to both heat and radiation.
Optimal recoveries in the low bacteria sample occurred at the 21% moisture level at 28 to 360C after a 5-
day incubation. The population increased more than four orders of magnitude under these conditions.
The indigenous salmonellae initiating this growth had survived in a desiccated state for over 1 year prior
to providing the proper moisture-temperature combination for the repopulation to occur. ---
as long as a demonstrated potential exists for repopulation of salmonellae in a commercial soil
amendment product produced from composted sludge, a potential health hazard exists for the user.
APPLIED AND ENVIRONMENTAL MICROBIOLOGY, Mar. 1981, p. 597-602
Evaluation of the Health Risks Associated with the Treatment and Disposal of Municipal Wastewater and Sludge (1981)
Compost worker - ear infection - Despite treatment, there was erosion of 70% of the right tympanic membrane. One
compost worker's x-ray exhibited an abnormality compatible with an occupationally-relate disorder.
Heat Dried Milorganite study
36. For both the annual and perennial fields the incidence of liver degeneration in the meadow vole did not differ
between the fertilized and sludge treated plots but was lower in the control plots.
37. Meadow voles from the sludge-treated annual field showed a more severe liver degeneration than those from the
sludge-treated perennial fields.
Evaluation of Health Risks Associated with Wastewater Treatment and Sewage Composting
excess of abnormal skin, nose and ear conditions, -- lab reports suggestive of low grade inflammatory response.
Former workers at the Metropolitan Sewage District in Chicago had excessive leukemia and esophagus deaths.
Regrowth of Salmonellae in Composted Sewage Sludge
decrease may only be temporary because this pathogen can survive and grow without a human host.
[the implication is that regrowth may be contributed to recontamination by birds]
Trace Organic and Inorganic in Distribution and Marking Municipal Sludges
[Class A Sludge -- aka Biosolids]
Efforts to characterize major unknown organic components were limited to computer comparisons of GC/MS peaks to
the NBS mass spectral library. In none of the cases was a tentative identification made. Manual review of those
components with a high degree of fit with an NBS library compound (>8O%) allowed probable compound class
assignment for many peaks. Virtually all of the major components classified appeared to be aliphatics or carboxylic acid
type compounds. A majority of the sample extracts exhibited a hydrocarbon "hump" in the ion
chromatograms. The peaks reviewed, therefore, were superimposed on this background. As a result, a significant
portion of the major peaks were multi-component peaks whose identities remain completely unknown.
Occurrence of Pathogens in Distribution and Marketing Municipal Sludges
[Class A Sludge -- aka Biosolids]
"Although the use of sludge as a soil amendment is attractive, it is not without potential health risks. Toxic
chemicals, including heavy metals and industrial organics, may enter the food chain and present long-term
health risks." The plague causing bacteria Yersinia (pestis?) was consistently found in static pile compost. CDC
authorities state, "Outbreaks in people still occur in rural communities or in cities." significant increases in bacterial
populations, including salmonellae, occurred during subsequent production of commercial soil amendment products.
Water Science and Technology Vol 31 No 5-6 pp 91–95 © IWA Publishing 1995
Pathogen die-off in stored wastewater sludge
The storage of wastewater sludge as a possible low-cost means of pathogen reduction prior to its beneficial reuse was
examined. However, after a 12 month storage period levels of Salmonella, faecal coliforms and streptococci, and
Giardia cysts were too high for simple storage to be considered an adequate treatment option.
"Pathogen Destruction and Biosolids Composting" in Biocycle of June of 1996,
"There is some evidence that coliforms and Salmonella sp. can survive prolonged exposure to temperatures of 55 C."
They cite a study done by Droffner and Brinton (1995) using DNA gene probes, where they detected E. coli and
Salmonella sp. in samples collected from an in-vessel composting facility after the first 15 days of active composting at
a temperature above 55 C. In Table 5-4 Processes to Further Reduce Pathogens in A Plain English Guide to the EPA
Part 503 Biosolids Rule, composting time and temperature requirements for within-vessel composting method was 55 C
or higher for three days! Droffner and Brinton found that it took 56 days and 90 days for the densities of Salmonella
sp. and E. Coli, respectively, to decline below the detection limit...These investigators also "cite evidence of mutant
strains of E. coli and Salmonella sp. resistant to thermal environments in composting." (p. 68)
Determination of Statement of Principles concerning EXTRINSIC ALLERGIC ALVEOLITIS ICD CODE: 495
Veterans’ Entitlements Act 1986
This Statement of Principles is about extrinsic allergic alveolitis and death from extrinsic allergic alveolitis.
For the purposes of this Statement of Principles, “extrinsic allergic alveolitis” means an immunologically induced
inflammation of the lung parenchyma involving mainly the alveoli and terminal bronchioles, which develops secondary
to repeated inhalation, by a sensitised subject, of any one of a variety of antigens, attracting ICD code 495.
Factors: inhaling, from an antigenic source, the specific antigen responsible for the extrinsic allergic alveolitis,
“antigen” means a substance which is capable of inducing an immune response and reacting with the specific
antibody or specifically sensitised T-lymphocytes which are the products of that response. Antigens may be
soluble substances, such as toxins and foreign proteins, or particulate such as bacteria and tissue cells. The major
categories of antigens causing extrinsic allergic alveolitis are microbial agents, animal proteins and low molecular
weight chemicals (haptens). Microbial contamination of various inhaled dusts is the commonest source of antigens;
“antigenic source” Sewage sludge contaminated with micro-organisms -- Fertilizer contaminated with micro-
organisms -- Compost dust contaminated with micro-organisms
Canada -- Document last updated on October 15, 2008
What is extrinsic allergic alveolitis?
The term extrinsic allergic alveolitis (EAA) refers to a group of lung diseases resulting from exposure to dusts of animal
and vegetable origin. The name, although complicated, describes the origin and the nature of these diseases.
"extrinsic"-- cause originating outside the body
"allergic"-- caused by the allergic reaction of the body to a specific substance or condition
"alveolitis"-- an inflammation in the inner part of the lungs (alveoli - small air sacs in the lungs)
How does extrinsic allergic alveolitis develop?
Extrinsic allergic alveolitis does not develop on the first day of exposure to animal and vegetable dusts. Repeated and
prolonged exposure is necessary. Even then, only some workers develop allergic reactions to the dusts. Ten to forty
percent (10 - 40%) of exposed people do not show any symptoms of extrinsic allergic alveolitis.
The allergy is triggered by complicated reactions of the body's natural defense system that normally protects the lungs
from foreign substances. In some individuals, the chemical reactions of the defense system that would ordinarily
protect the lungs actually cause the inflammation and lung damage. The body's changing response to the presence of
dust in the lungs is called sensitization.
What are the symptoms of extrinsic allergic alveolitis?
Extrinsic allergic alveolitis, once a person is sensitized, can show three different types of responses: acute (intense)
response, sub-acute (recurrent) response, and chronic (long-term) response.
The acute attack begins by heavy exposure to the trigger. It starts with fever, muscular aches and a general, unwell
feeling or malaise. These symptoms are accompanied by tightness in the chest, a dry cough, and shortness of breath.
Symptoms may develop between 4 and 12 hours after exposure.
The sub-acute response occurs most frequently to people exposed to relatively low levels of dust. It is marked by
cough, shortness of breath, sweating, sore throat, headache, and nausea.
The chronic response develops after persistent acute attacks and recurrent sub-acute responses. It is marked by
increasing shortness of breath, occasional fever, loss of weight, and general lack of energy. The victim suffers
permanent lung damage and, in the worst cases, death may occur.
The name of one disease and cause: Sewage sludge disease -- Dust of heat-treated sludge
Water Science and Technology Vol 35 No 11-12 pp 269–275 © IWA Publishing 1997
Regrowth of faecal coliforms and salmonellae in stored biosolids and soil amended with biosolids
Stabilised wastewater sludge (biosolids) has beneficial re-use properties but these are limited by the presence of
human pathogens. In two storage trials biosolids were stored in piles 1m high and monitored for <60 weeks. Included in
the monitoring programme were tests to determine the concentrations of faecal coliforms, faecal streptococci and
salmonellae. In both the soil amendment trials and biosolids storage trials, concentrations of indicator organisms and
salmonellae decreased through an extended hot, dry summer period. Although these organisms were not detected in
the majority of samples taken during the summer, repopulation of faecal coliforms and salmonellae occurred in
the trials following rainfall at the beginning of the winter. In the case of one of the storage trials repopulation
occurred following a period of 50 weeks when salmonellae and faecal coliforms were not detected. When
repopulation occurred, faecal coliform concentrations increased to higher than those at the beginning of
the trials. These results suggest that faecal coliforms and salmonellae were at undetectable concentrations through
the summer period but were able to grow when provided with favourable conditions. From this limited trial it was
concluded that soil amended with biosolids could not be considered free from pathogens for at least one year following
Montgomery County, Maryland A State-of-the-Art Biosolids Composting Facility
Editors Note: The Montgomery County, MD, Biosolids Composting Facility was closed on May 1, 1999.
The pressure to commercially develop the strategically located County property where the project was
sited combined with odor complaints from a community undergoing significant demographic changes
appeared to be the cause of the closure. -- The Blue Plains wastewater treatment plant is located on the banks of the
Potomac River adjacent to Washington, D.C.
Millions of people have appreciated the landscaping benefits of the Compro product
without even realizing it. Compro is used on some of the most high-profile lawns and gardens in the country;
including, the White House, Mount Vernon, the Governor’s Mansion in Annapolis, Maryland and the
celebrated Orioles Park at Camden Yards in Baltimore. When Tiger Woods and the rest of the 1997 U.S.
Open Tour strode the fairways at Congressional Country Club in Potomac, MD, they were walking on grass
fed with Compro.
Maryland Environmental Services (MES). Established in the early 1970's, MES is a not-for-profit organization spun
off from the Maryland Department of Natural Resources (DNR) to manage wastewater treatment and
drinking water plants. The idea was to separate enforcement - the DNR’s job - from the operation of such facilities.
When the MCRCF came on line, MES took over marketing the compost products.
A High-Level Disinfection Standard for Land-Applied Sewage Sludges (Biosolids)
The potential for pathogen regrowth is the downside to sewage sludge being rich innutrients that promote the
growth of bacteria and fungi.Exotoxins;"proteins and peptides secreted into the surrounding environment by growing
cells",are produced by both gram-negative and gram-positive bacteria. They are usually the most toxic of the two
general types of bacterial toxins. Because they can retain their toxicity at extremely high dilutions, some exotoxins,
including staphylococcal enterotoxins and shigatoxin, are used as biological warfare agents. Traces of endotoxins in
food and water can cause headaches, fever, fatigue, and severe gastrointestinal symptoms; however, their primary
target is the lungs. In addition to the former symptoms, inhaling endotoxin-contaminated dusts can cause acute airflow
obstruction, shock, and even death.
EPA acknowledges that Biosolids Compost may be hazardous to your Health in the 2006
Biosolids Technology Fact Sheet: Use of Composting for Biosolids Management
of the compost product
- Potential environmental impacts may result from both composting operations and use
volatile organic compounds, must also be controlled
- Composting is not a sterilization process and a properly composted product maintains an active population of
beneficial microorganisms that compete against the pathogenic members. Under some conditions, explosive
regrowth of pathogenic microorganisms is possible.
- In addition to odors, other bioaerosols, such as pathogens, endotoxins, and various
- Survival and presence of primary pathogens in the product.
- Dispersion of secondary pathogens such as Aspergillus fumigatus, particulate matter, other airborne allergens
- The spores of A. fumigatus counts at composting facilities are high, and-- persons handling composted biosolids
being exposed to these spores is also high (Epstein, 1998).
- While healthy individuals may not be affected, immunocompromised individuals may be at risk.
- These organisms can potentially invade a normal, healthy human being and produce illness or debilitation
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San Francisco claims sludge compost, aka biosolids, will help
grow healthy plants, fruits and vegetables. It will even give you
this hazardous waste it calls a valuable fertilizer for nothing.