mitigating the effects of chemotherapy drugs at camp oochigeas · mitigating the effects of...
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Mitigating the Effects of Chemotherapy Drugs atCamp OochigeasPresentation by:Kathryn Stasiuk, EIT Michael Varty, [email protected] [email protected]
Outline→ Camp Oochigeas
→ Design Background
→ Chemotherapy
Drugs
→ Discussion
→ Monitoring Results
→ Challenges and
Opportunities
→ Questions
Camp Oochigeas
Background on Camp Oochigeas
→ Summer Camp for Children Affected by Cancer→ Privately funded (registered
charity), volunteer-run camp → Camp located in Rosseau, ON
(West of Hunstville)→ Annual “Sporting for Life” 10k
run in Toronto held to support camp operations
→ In 2015, the camp made the decision to expand the capacity from 200 to 400 people
Design Background Problem
Statement
All kids who attend camp have been affected by cancer, and a percentage of the campers would be administered chemotherapy drugs while at camp.
WSP was required to determine the possible negative impacts of the drugs on the treatment capabilities of the sewage system.
Two (2) types of drugs are administered the most for Ooch campers: Cytostaticsand Vinca Alkaloids.
Design Background
Methodology→ WSP coordinated with the Hospital for Sick
Children in Toronto for chemo details:
→ Type of chemotherapy drugs most commonly used,
→ Frequency to which they are used, and
→ The number of campers that may be on an active
cycle at any time.
→ Given the Additional Details on
Chemotherapy:
→ WSP collaborated with the treatment service
provider (RH2O North America) to approximate the
impact on their treatment technologies.
Design Background
Background and Assumptions → Cytostatic drugs are
commonly present in the camp wastewater
→ Frequency of Dosage Estimated by Sick Kids Toronto→ 18 total doses in 2011→ 14 total doses in 2012→ 8 total doses in 2013→ Estimated “2-5 doses in any
given week”
→ Assumptions:→ Maximum doses
administered→ Up to five (5) children
administered chemo per week
Chemotherapy
Cytostatic Drugs
→ Cytostatic (or Cytotoxic) drugs such as the two (2) Antimetabolites:→ Methotrexate (30 mg/L max) [1]
→ Mercaptopurine (50 mg/L max) [2]
→ Mechanism→ “Antimetabolites” have similar structures to
metabolites in the body (such as folic acid) [2]
→ They have toxic effects on cell division by inhibiting DNA synthesis. [2]
→ Half lives are:→ Mercaptopurine (50 minutes) [3]
→ Methotrexate (3 – 10 hours) [3]
Mercaptopurine
Methotrexate
Note: all chemical formulae from Wikipedia
Chemotherapy
Vinca Alkaloids
→ Vinca Alkaloids are anti-tumour drugs that disrupts the “mitotic spindle assembly” to inhibit mitosis (cell-division)[4][5]
→ The two Vinca Alkaloids used are derived from the Madagascar rosy periwinkle→ Vincristine (2 mg/L max) [4]
→ Vinblastine (6.5 mg/L max) [5]
→ Half Life→ Vincristine (average 85 hours) [4]
→ Vinblastine (25 hours) [5]
Image Source: WikipediaVincristine Vinblastine
Sewage System Design
Cytostatic Drugs
95% removal@ t = 4 hours
Methotrexate
-10
0
10
20
30
40
50
60
0 10 20 30 40 50
Co
nce
ntr
atio
n (m
g/L
)
Time (Hours)
Decay of Cytostatic Drugs
Methotrexate Concentration (mg/L) Mercaptopurine Concentration (mg/L)
Mercaptopurine
95% removal@ t = 43 hours
Sewage System Design
Vinca Alkaloids
0
1
2
3
4
5
6
7
0 2 4 6 8 10 12 14 16 18
Co
nce
ntr
atio
n (m
g/L
)
Time (Days)
Decay of Vinca Alkaloids
Vincristine Vinblastine95% removal@ t = 15 days
Vincristine
95% removal@ t = 4.5 days
Vinblastine
Sewage System Design
Retention TimeRetention capacity available prior to the bioreactor is 126,400 L
Average flows in 2017: approximately 22,000 L/day
At least 5.7 days of retention prior to entry into Bioreactors
Sewage System Design
Discussion
95% removal@ t = 15 days
Vincristine
→ Trash tanks throughout camp increase overall retention time
→ Vincristine excretion rate and mechanisms→ 70-90% in feces
→ 10-30% in urine
→ Time delayed excretion
Time Excretion*
(Hours) (Percent)0 - 24 12.7%24 - 48 13.3%48 - 72 6.7%72 - 90 4.0%
*Urinary [6]
67% removal of vincristine in t = 5.7 days
Monitoring Results
System Operation: 2017 ResultsPARAMETERS RAW SEWAGE (mg/L)
Sampling Event June 28 August 31BOD 52 270TSS 42 99TKN 49 121Total Phosphorus 4.8 13.8Ammonia-N 47 86Nitrite <0.01 <0.10Nitrate <0.10 <0.20Alkalinity (as CaCO3) 290 486pH 7.81 7.45
PARAMETERS TREATED EFFLUENT (mg/L)
Sampling Event EFFLUENT OBJECTIVE June 28 August 31
CBOD 10(1) <2 <3
TSS 10(1) 16 28.6
Total Phosphorus 1.0(1) 1.1 2.7
TKN - 5.4 7.44
Ammonia-N - 5.4 5.04
Nitrite - 3.4 0.11
Nitrate - 54.8 43
Alkalinity (as CaCO3) - <1.0 <1.0
pH - 5.06 4.27
(1) Bold concentrations are exceedances of the effluent objectives
Challenges → Evaluating Impact→ The Laboratories approached in Ontario did not offer
testing for chemotherapy drugs
→ Rounds of chemotherapy drugs administered can vary throughout summer
→ Estimation of the time between drug administration and entry into the sewage system adds unknowns
→ ECA Requirements→ Treated effluent objective of <1.0 mg/L for Total
Phosphorus
→ Any changes to the system operation requires ECA amendment
→ Experimental treatment solutions do not work well with an ongoing ECA and monitoring process
Opportunities→ Innovation Opportunities
→ Chemotherapy drugs are not tested regularly at environmental labs – however some labs have offered to develop these tests
→ Field testing the operational effects of chemotherapy drugs in an on-site context could be of value to treatment providers of various scales
→ Research Opportunities→ Research into the potential impact of chemotherapy
drugs is beginning on a macro/municipal scale: having a unique site of this nature could allow for field testing that is not possible for municipalities
→ Treatment of Contaminants of Emerging Concern (CEC)s can be researched in a controlled environment
Questions?
Sources
[1] Pub Chem: Methotrexate https://pubchem.ncbi.nlm.nih.gov/compound/126941[2] Pub Chem: Mercaptopurinehttps://pubchem.ncbi.nlm.nih.gov/compound/667490[3] J. Zhang et al., Removal of cytostatic drugs from aquatic environment: A review. Science of the Total Environment 445-446 (2013) 289-298[4] Pub Chem: Vincristine Sulfatehttps://pubchem.ncbi.nlm.nih.gov/compound/5388992#section=Top[5] Pub Chem: Vinblastinehttps://pubchem.ncbi.nlm.nih.gov/compound/241903#section=Top[6] Sethi & Kimball, Pharmaokinetics of Vincristine Sulfate in Children. Cancer Chemother Pharmacol (1981) 6: 111-115
