# Anatomical Distribution of Diarrhetic Shellfish Toxins (DSTs) in the Japanese Scallop Patinopecten yessoensis and Individual Variability in Scallops and Mytilus edulis Mussels: Statistical Considerations

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## Abstract

**:**

**Key Contribution:**This is the first detailed analysis of the distribution of individual concentrations of DSTs in shellfish samples, as well as the first report of a method for analyzing and evaluating the relationship between the individual concentrations and mean population concentrations based on statistical methods.

## 1. Introduction

## 2. Results

#### 2.1. Concentrations and Distribution of DSTs

#### 2.1.1. Anatomical Compartmentalization of DST in Scallops

#### 2.1.2. DST Analysis of 30 Individual Scallops and Mussels

#### 2.1.3. Analysis of DST Concentration in Scallop Samples from Different Water Depths

#### 2.2. Statistical Analysis

#### 2.2.1. Statistical Resampling Analysis of DSTs in Scallops and Mussels

#### 2.2.2. Estimating the Mean Concentration of the Population (Cultured Scallops) When the Individual Concentration of a Sample Is Defined

**[13]**.

_{0.05}(∞) and hence is generalized with ${t}_{\alpha}\left(\nu \right)$.

_{0.05}(9) = 2.2622 from the Student’s t-distribution in Table 6 was assigned in Equation (3).

**s**was estimated using t

_{0.05}(9) = 2.2622 from Student’s t-distribution table.

**s**is less than or equal to the graph value (striped zone of Figure 7), it is considered that the mean concentration of $\mu $ can be estimated with an interval of ±160 ng/g and 90% or 95% confidence.

#### 2.2.3. Adequacy of Sample Size Based on the t-Value and Confidence Interval

_{0.10}(∞) = 1.6449 or t

_{0.05}(∞) = 1.9600 equal to the standard normal distribution at each confidence level). When t = 0.05 or 0.10, points of n = 20, 25, 30 and approximate straight lines are drawn on a t-value graph (Figure 8, red double lines). Although the coefficient of approximate straight lines varies depending on the desired value and confidence, the risk of the obtained estimation value is greatly reduced as the sample size increases and the t-value approaches each linear approximation.

_{0.10}(100) and t

_{0.10}(∞) or that between t

_{0.05}(100) and t

_{0.05}(∞) is 0.0153 or 0.024, respectively (Table 6). These levels are within a margin of error that does not matter practically. The ideal number of samples is 14 (ν = 13) or more, but considering the mathematical errors, 13 (ν = 12) or more samples is assumed to be a practical allowable range.

## 3. Discussion

_{0.10}(∞) = 1.6449 or y = t

_{0.05}(∞) = 1.9600). The larger the sample size, the better, but in practice there are many cases where statistical ideals are not satisfied due to various restrictions. In the case of scallops or mussels, calculation of an approximate expression using an impractically large size of samples is irrational and not applicable to real-world conditions. Hence, the linear approximate expression at each reliability (α = 0.10 or 0.05) was calculated using samples of 20, 25, and 30 in this study (Figure 8). Samples of about 14 or more for scallops or mussels were derived as ideal sample sizes as the result of the estimation from Figure 8. Because the graph of f(t, ν = 100) and the standard normal distribution f(t, ν = ∞) are almost identical (Figure 9), 13 or more samples are considered to be a practical preferred range including mathematical errors.

## 4. Materials and Methods

#### 4.1. Plankton Monitoring

#### 4.2. Scallops and Mussels

#### 4.3. Extraction of DSTs and Hydrolysis of Esterified DSTs

#### 4.4. Standard Toxins

#### 4.5. LC/MS/MS Analysis of DSTs

^{−}as target parent ions in Q1 and particular fragment ions of each toxin in Q3, with a dwell time of 100 ms for each analogue as follows. OA: m/z 803.5 > 255.3; DTX1: m/z 817.5 > 255.3. LoD (limit of detection) of OA and DTX1 < 0.01 mg/kg. The proportion of the DTX1 quantity corresponding to each tissue was calculated by multiplying the concentrations by the total tissue weight.

#### 4.6. Statistical Analyses

- N = number of individuals in the population.
- n = number of individuals in the sample.

- Two-tailed significance level (α) = 0.05 or 0.10.
- Confidence level = 1 − α.
- Confidence interval (CI) = 100 (1 − α)%.
- Statistical degrees of freedom = n − 1 = Greek letter nu (ν).

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**Concentrations of DTX1 and OA in the digestive glands of scallops. Fourteen to twenty individuals were combined into each sample set used for analysis. Black bars and white bars represent DTX1 and OA, respectively. The concentrations of toxins in the samples are shown on the vertical axis.

**Figure 3.**The 30 individual distributions, means ± σ of DTX1 in scallops and mussels. Panels (

**a**–

**d**) show the results for scallops and (

**e**–

**g**) show those for mussels.

**Figure 5.**The distributions of scallop at each depth on 28 June and 11 August. The mean concentrations of DTX1 ± σ are shown for (

**a**–

**d**) 28 June and (

**e**–

**h**) 11 August.

**Figure 6.**Vertical distributions of Dinophysis species. (

**a**) D. acuminata; (

**b**) D. fortii and other Dinophysis species.

**Figure 7.**Estimation of s with the mean density of $\mu $ within interval ±160 ng/g at (

**a**) 95% or (

**b**) 90% confidence. The X axis n represents a sample size of 3–20.

**Figure 8.**The t-value of α = 0.05 or 0.10 with ν = 2–30. (

**a**) Triangles are t

_{0.05}(2–30); (

**b**) diamonds are t

_{0.10}(2–30). The dotted lines show (

**a**) y = 1.9600 and (

**b**) y = 1.6449. The red circles represent the t-values of n = (20, 25, 30) at α = 0.05 or 0.10, and red double lines approximate the straight line of each t

_{0.05}(20, 25, 30) and t

_{0.10}(20, 25, 30). The red equations on the graph represent a linear approximation line of t-values.

**Figure 9.**Overlay graphs of f(t, ν = 30, 50, and 100) red lines, and the standard normal distribution f(t, ν = ∞) black lines. (

**a**) f(t, ν =30) and f(t, ν = ∞); (

**b**) f(t, ν = 50) and f(t, ν = ∞); (

**c**) f(t, ν = 100) and f(t, ν = ∞).

2014 | 26 May | 2 June | 9 June | 30 June | 14 July | 22 July | 28 July |
---|---|---|---|---|---|---|---|

Number of Individuals | 16 | 18 | 17 | 18 | 15 | 20 | 14 |

Digestive gland | 72.90 | 72.87 | 72.97 | 70.80 | 60.80 | 75.16 | 58.56 |

Gonad | 42.39 | 39.99 | 40.79 | 44.22 | 48.05 | 54.46 | 39.83 |

Mantle | 155.01 | 151.37 | 163.48 | 175.80 | 163.66 | 213.96 | 169.30 |

Gill | 95.31 | 93.43 | 106.28 | 92.20 | 87.08 | 116.42 | 85.49 |

Adductor muscle | 301.69 | 315.19 | 311.42 | 355.14 | 318.80 | 434.35 | 340.26 |

**Table 2.**Sampling information and mean weight (g) of the digestive glands of 30 scallops or mussels. The mean values of 30 samples ± population standard deviation (σ).

2014 | 26 May | 2 June | 9 June | 16 June | 7 July | 8 August |
---|---|---|---|---|---|---|

Scallop (Digestive gland/Whole meat %) | 3.87 ± 1.07 (10.14%) | 3.62 ± 0.81 (10.56%) | 3.70 ± 0.98 (8.78%) | 3.81 ± 0.72 (9.18%) | - | - |

Mussel (Digestive gland/Whole meat %) | - | 1.69 ± 0.45 (14.72%) | - | - | 1.40 ± 0.46 (14.89%) | 1.51 ± 0.45 (12.90%) |

**Table 3.**Sampling information and mean weight (g) of scallop digestive glands. The mean value of digestive glands ± σ at each depth.

2016 | 18 May | 28 June | 11 August |
---|---|---|---|

Number of Individuals | 10 | 15 | 15 |

5 m | 6.45 ± 1.24 | 4.77 ± 0.82 | 1.40 ± 0.36 |

10 m | 6.16 ± 0.91 | 5.18 ± 1.33 | 1.38 ± 0.26 |

15 m | 5.30 ± 0.45 | 4.22 ± 0.75 | 1.46 ± 0.42 |

Transparency (m) | Date (2016) | Depth (m) | Water Temperature (°C) | Salinity (psu) | D. fortii (Cells/L) | D. acuminate (Cells/L) | Other Dinophysis (Cells/L) | |
---|---|---|---|---|---|---|---|---|

18 May | 0 | 11.2 | 30.84 | 0 | 30 | 0 | ||

5 | 9.7 | 31.98 | 0 | 60 | 0 | |||

5.0 | 10 | 9.2 | 32.03 | 0 | 100 | 0 | ||

15 | 8.1 | 32.32 | 0 | 80 | 0 | |||

20 | 7.8 | 32.59 | 0 | 30 | 0 | |||

25 | 7.4 | 32.67 | 0 | 90 | 0 | |||

30 | 7.3 | 32.70 | 0 | 150 | 0 | |||

28 June | 0 | 16.6 | 29.58 | 0 | 1120 | 0 | ||

5 | 14.8 | 31.15 | 30 | 650 | 60 | Dt60 | ||

4.0 | 10 | 13.7 | 31.94 | 180 | 740 | 190 | Dn150, Dt40 | |

15 | 13.4 | 32.09 | 30 | 490 | 80 | Dn60, Dr20 | ||

20 | 13.0 | 32.18 | 40 | 300 | 10 | Dr10 | ||

25 | 12.8 | 32.22 | 0 | 70 | 10 | Dn10 | ||

30 | 12.3 | 32.33 | 0 | 50 | 10 | Dn10 | ||

11 August | 0 | 22.6 | 31.14 | 0 | 0 | 0 | ||

5 | 20.7 | 31.67 | 0 | 0 | 50 | Dt50 | ||

10.5 | 10 | 16.9 | 32.37 | 0 | 10 | 30 | Dt30 | |

15 | 12.7 | 32.64 | 0 | 0 | 30 | Dt20, Dr10 | ||

20 | 10.8 | 32.95 | 10 | 0 | 0 | |||

25 | 8.6 | 32.95 | 50 | 0 | 10 | Dt10 | ||

30 | 7.9 | 33.02 | 90 | 20 | 0 |

**Table 5.**Resampling analysis of scallops and mussels without replacement and with the bootstrap method. The left half of the table is a resampling analysis without replacement, while the right half shows the data using the bootstrap method. The n columns represent 5–25 samples. 1 to 99 represent percentiles. Percentage: each percentile columns represents the mean value of a data set for each mean of the 30 individuals. >±30; <±30; <±

**20**; <±

**10**.

Scallop | Mussel | Scallop | Mussel | ||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|

n | 1 | 5 | 95 | 99 | 1 | 5 | 95 | 99 | n | 1 | 5 | 95 | 99 | 1 | 5 | 95 | 99 |

5 | 75.6 | 82.1 | 119.0 | 126.3 | 49.5 | 60.4 | 144.4 | 163.7 | 5 | 72.5 | 80.7 | 120.7 | 130.3 | 44.3 | 58.2 | 149.8 | 172.0 |

6 | 77.7 | 84.0 | 117.0 | 123.7 | 52.0 | 63.9 | 139.4 | 155.8 | 6 | 75.6 | 82.3 | 118.8 | 127.2 | 48.8 | 61.3 | 144.6 | 164.2 |

7 | 80.0 | 85.4 | 114.9 | 120.4 | 56.2 | 66.9 | 134.8 | 148.8 | 7 | 76.6 | 83.5 | 116.8 | 124.4 | 51.3 | 63.8 | 139.8 | 157.2 |

8 | 81.1 | 86.5 | 113.9 | 119.0 | 58.5 | 69.5 | 132.6 | 144.4 | 8 | 78.4 | 84.7 | 115.7 | 122.9 | 54.9 | 66.5 | 137.3 | 154.3 |

9 | 82.9 | 87.6 | 112.9 | 117.6 | 61.9 | 71.8 | 129.8 | 140.3 | 9 | 79.2 | 85.5 | 114.3 | 121.1 | 56.5 | 67.8 | 133.9 | 150.0 |

10 | 84.4 | 88.5 | 111.6 | 116.0 | 64.1 | 73.7 | 126.9 | 138.6 | 10 | 80.7 | 86.3 | 114.0 | 120.1 | 59.4 | 69.8 | 132.6 | 147.9 |

11 | 85.5 | 89.3 | 111.0 | 114.7 | 67.0 | 75.9 | 124.8 | 135.4 | 11 | 81.4 | 86.8 | 113.3 | 119.1 | 60.6 | 70.4 | 131.4 | 145.4 |

12 | 86.1 | 89.8 | 110.4 | 114.1 | 69.4 | 77.4 | 123.7 | 132.1 | 12 | 82.4 | 87.4 | 112.9 | 118.8 | 62.5 | 72.0 | 130.7 | 144.1 |

13 | 87.4 | 90.7 | 109.4 | 112.9 | 70.6 | 78.5 | 121.6 | 129.7 | 13 | 82.9 | 87.9 | 112.2 | 117.6 | 63.5 | 73.0 | 128.8 | 140.9 |

14 | 87.8 | 91.2 | 108.6 | 112.1 | 72.5 | 79.7 | 119.9 | 127.7 | 14 | 83.6 | 88.5 | 112.1 | 117.4 | 65.3 | 74.2 | 128.7 | 140.8 |

15 | 88.7 | 91.7 | 108.0 | 111.1 | 74.2 | 81.2 | 118.9 | 126.3 | 15 | 84.5 | 88.9 | 111.6 | 116.3 | 65.6 | 75.1 | 126.8 | 137.8 |

16 | 89.7 | 92.5 | 107.6 | 110.3 | 75.0 | 82.2 | 117.5 | 124.2 | 16 | 84.6 | 89.2 | 111.0 | 115.6 | 66.8 | 75.9 | 126.0 | 136.9 |

17 | 90.0 | 92.8 | 107.1 | 109.7 | 77.6 | 83.7 | 116.5 | 122.4 | 17 | 85.1 | 89.5 | 110.7 | 115.1 | 67.2 | 76.6 | 124.9 | 136.2 |

18 | 90.8 | 93.2 | 106.5 | 109.1 | 78.5 | 84.8 | 115.1 | 120.4 | 18 | 85.8 | 89.8 | 110.6 | 115.2 | 68.9 | 77.2 | 124.3 | 135.3 |

19 | 91.4 | 93.6 | 106.2 | 108.4 | 80.0 | 85.6 | 113.8 | 119.2 | 19 | 86.0 | 90.0 | 110.2 | 114.7 | 69.9 | 77.5 | 123.9 | 134.4 |

20 | 92.0 | 94.0 | 105.8 | 107.8 | 81.1 | 86.7 | 112.9 | 117.3 | 20 | 85.8 | 90.2 | 109.9 | 114.0 | 69.5 | 78.0 | 123.2 | 133.6 |

21 | 92.6 | 94.5 | 105.2 | 107.2 | 82.2 | 87.4 | 111.9 | 116.0 | 21 | 86.8 | 90.6 | 109.6 | 113.9 | 70.5 | 78.8 | 122.6 | 132.3 |

22 | 93.1 | 94.9 | 104.9 | 106.6 | 83.7 | 88.4 | 110.8 | 114.5 | 22 | 87.1 | 90.8 | 109.4 | 113.6 | 71.0 | 79.2 | 122.0 | 132.7 |

23 | 93.5 | 95.2 | 104.5 | 106.3 | 84.7 | 89.2 | 110.1 | 113.5 | 23 | 87.2 | 91.0 | 109.3 | 113.2 | 72.0 | 79.8 | 121.6 | 131.1 |

24 | 94.1 | 95.7 | 104.0 | 105.5 | 86.1 | 90.2 | 108.8 | 111.7 | 24 | 87.4 | 91.0 | 109.2 | 113.0 | 72.3 | 79.9 | 121.3 | 130.5 |

25 | 94.6 | 96.1 | 103.6 | 105.0 | 87.3 | 91.1 | 107.9 | 110.3 | 25 | 88.0 | 91.3 | 109.1 | 113.1 | 73.3 | 80.5 | 121.1 | 130.4 |

ν | Two-Tailed Probability | |
---|---|---|

0.10 | 0.05 | |

2 | 2.9200 | 4.3027 |

3 | 2.3534 | 3.1824 |

4 | 2.1318 | 2.7764 |

5 | 2.0150 | 2.5706 |

6 | 1.9432 | 2.4469 |

7 | 1.8946 | 2.3646 |

8 | 1.8595 | 2.3060 |

9 | 1.8331 | 2.2622 |

10 | 1.8125 | 2.2281 |

11 | 1.7959 | 2.2010 |

12 | 1.7823 | 2.1788 |

13 | 1.7709 | 2.1604 |

14 | 1.7613 | 2.1448 |

15 | 1.7531 | 2.1314 |

16 | 1.7459 | 2.1199 |

17 | 1.7396 | 2.1098 |

18 | 1.7341 | 2.1009 |

19 | 1.7291 | 2.0930 |

20 | 1.7247 | 2.0860 |

21 | 1.7207 | 2.0796 |

22 | 1.7171 | 2.0739 |

23 | 1.7139 | 2.0687 |

24 | 1.7109 | 2.0639 |

25 | 1.7081 | 2.0595 |

26 | 1.7056 | 2.0555 |

27 | 1.7033 | 2.0518 |

28 | 1.7011 | 2.0484 |

29 | 1.6991 | 2.0452 |

30 | 1.6973 | 2.0423 |

50 | 1.6759 | 2.0086 |

100 | 1.6602 | 1.9840 |

∞ | 1.6449 | 1.9600 |

**Table 7.**Interval estimation (±OA group ng/g digestive gland) of $\mu $ in α = 0.05. The n columns represent sample size 3–20 samples. Rows from 100 to 650 represent the s values.

n | t (α = 0.05) | Sample Standard Deviation (s) | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|

100 | 150 | 200 | 250 | 300 | 350 | 400 | 450 | 500 | 550 | 600 | 650 | ||

3 | 4.3027 | 248.4 | 372.6 | 496.8 | 621.0 | 745.2 | 869.5 | 993.7 | 1117.9 | 1242.1 | 1366.3 | 1490.5 | 1614.7 |

4 | 3.1825 | 159.1 | 238.7 | 318.3 | 397.8 | 477.4 | 556.9 | 636.5 | 716.1 | 795.6 | 875.2 | 954.8 | 1034.3 |

5 | 2.7764 | 124.2 | 186.2 | 248.3 | 310.4 | 372.5 | 434.6 | 496.7 | 558.7 | 620.8 | 682.9 | 745.0 | 807.1 |

6 | 2.5706 | 104.9 | 157.4 | 209.9 | 262.4 | 314.8 | 367.3 | 419.8 | 472.2 | 524.7 | 577.2 | 629.7 | 682.1 |

7 | 2.4469 | 92.5 | 138.7 | 185.0 | 231.2 | 277.5 | 323.7 | 369.9 | 416.2 | 462.4 | 508.7 | 554.9 | 601.1 |

8 | 2.3646 | 83.6 | 125.4 | 167.2 | 209.0 | 250.8 | 292.6 | 334.4 | 376.2 | 418.0 | 459.8 | 501.6 | 543.4 |

9 | 2.3060 | 76.9 | 115.3 | 153.7 | 192.2 | 230.6 | 269.0 | 307.5 | 345.9 | 384.3 | 422.8 | 461.2 | 499.6 |

10 | 2.2622 | 71.5 | 107.3 | 143.1 | 178.8 | 214.6 | 250.4 | 286.1 | 321.9 | 357.7 | 393.5 | 429.2 | 465.0 |

11 | 2.2281 | 67.2 | 100.8 | 134.4 | 167.9 | 201.5 | 235.1 | 268.7 | 302.3 | 335.9 | 369.5 | 403.1 | 436.7 |

12 | 2.2010 | 63.5 | 95.3 | 127.1 | 158.8 | 190.6 | 222.4 | 254.1 | 285.9 | 317.7 | 349.5 | 381.2 | 413.0 |

13 | 2.1788 | 60.4 | 90.6 | 120.9 | 151.1 | 181.3 | 211.5 | 241.7 | 271.9 | 302.1 | 332.4 | 362.6 | 392.8 |

14 | 2.1604 | 57.7 | 86.6 | 115.5 | 144.3 | 173.2 | 202.1 | 231.0 | 259.8 | 288.7 | 317.6 | 346.4 | 375.3 |

15 | 2.1448 | 55.4 | 83.1 | 110.8 | 138.4 | 166.1 | 193.8 | 221.5 | 249.2 | 276.9 | 304.6 | 332.3 | 360.0 |

16 | 2.1315 | 53.3 | 79.9 | 106.6 | 133.2 | 159.9 | 186.5 | 213.2 | 239.8 | 266.4 | 293.1 | 319.7 | 346.4 |

17 | 2.1199 | 51.4 | 77.1 | 102.8 | 128.5 | 154.2 | 180.0 | 205.7 | 231.4 | 257.1 | 282.8 | 308.5 | 334.2 |

18 | 2.1098 | 49.7 | 74.6 | 99.5 | 124.3 | 149.2 | 174.0 | 198.9 | 223.8 | 248.6 | 273.5 | 298.4 | 323.2 |

19 | 2.1009 | 48.2 | 72.3 | 96.4 | 120.5 | 144.6 | 168.7 | 192.8 | 216.9 | 241.0 | 265.1 | 289.2 | 313.3 |

20 | 2.0930 | 46.8 | 70.2 | 93.6 | 117.0 | 140.4 | 163.8 | 187.2 | 210.6 | 234.0 | 257.4 | 280.8 | 304.2 |

**Table 8.**Interval estimation (±OA group ng/g digestive gland) of $\mu $ in α = 0.10. The n columns represent sample size 3–20. Rows 100 to 650 represent the s values.

n | t (α = 0.10) | Sample Standard Deviation (s) | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|

100 | 150 | 200 | 250 | 300 | 350 | 400 | 450 | 500 | 550 | 600 | 650 | ||

3 | 2.9200 | 168.6 | 252.9 | 337.2 | 421.5 | 505.8 | 590.1 | 674.3 | 758.6 | 842.9 | 927.2 | 1011.5 | 1095.8 |

4 | 2.3534 | 117.7 | 176.5 | 235.3 | 294.2 | 353.0 | 411.8 | 470.7 | 529.5 | 588.4 | 647.2 | 706.0 | 764.9 |

5 | 2.1318 | 95.3 | 143.0 | 190.7 | 238.3 | 286.0 | 333.7 | 381.3 | 429.0 | 476.7 | 524.4 | 572.0 | 619.7 |

6 | 2.0150 | 82.3 | 123.4 | 164.5 | 205.7 | 246.8 | 287.9 | 329.0 | 370.2 | 411.3 | 452.4 | 493.6 | 534.7 |

7 | 1.9432 | 73.4 | 110.2 | 146.9 | 183.6 | 220.3 | 257.1 | 293.8 | 330.5 | 367.2 | 404.0 | 440.7 | 477.4 |

8 | 1.8946 | 67.0 | 100.5 | 134.0 | 167.5 | 201.0 | 234.4 | 267.9 | 301.4 | 334.9 | 368.4 | 401.9 | 435.4 |

9 | 1.8595 | 62.0 | 93.0 | 124.0 | 155.0 | 186.0 | 216.9 | 247.9 | 278.9 | 309.9 | 340.9 | 371.9 | 402.9 |

10 | 1.8331 | 58.0 | 87.0 | 115.9 | 144.9 | 173.9 | 202.9 | 231.9 | 260.9 | 289.8 | 318.8 | 347.8 | 376.8 |

11 | 1.8125 | 54.6 | 82.0 | 109.3 | 136.6 | 163.9 | 191.3 | 218.6 | 245.9 | 273.2 | 300.6 | 327.9 | 355.2 |

12 | 1.7959 | 51.8 | 77.8 | 103.7 | 129.6 | 155.5 | 181.5 | 207.4 | 233.3 | 259.2 | 285.1 | 311.1 | 337.0 |

13 | 1.7823 | 49.4 | 74.1 | 98.9 | 123.6 | 148.3 | 173.0 | 197.7 | 222.4 | 247.2 | 271.9 | 296.6 | 321.3 |

14 | 1.7709 | 47.3 | 71.0 | 94.7 | 118.3 | 142.0 | 165.7 | 189.3 | 213.0 | 236.6 | 260.3 | 284.0 | 307.6 |

15 | 1.7613 | 45.5 | 68.2 | 91.0 | 113.7 | 136.4 | 159.2 | 181.9 | 204.6 | 227.4 | 250.1 | 272.9 | 295.6 |

16 | 1.7530 | 43.8 | 65.7 | 87.7 | 109.6 | 131.5 | 153.4 | 175.3 | 197.2 | 219.1 | 241.0 | 263.0 | 284.9 |

17 | 1.7459 | 42.3 | 63.5 | 84.7 | 105.9 | 127.0 | 148.2 | 169.4 | 190.5 | 211.7 | 232.9 | 254.1 | 275.2 |

18 | 1.7396 | 41.0 | 61.5 | 82.0 | 102.5 | 123.0 | 143.5 | 164.0 | 184.5 | 205.0 | 225.5 | 246.0 | 266.5 |

19 | 1.7341 | 39.8 | 59.7 | 79.6 | 99.5 | 119.3 | 139.2 | 159.1 | 179.0 | 198.9 | 218.8 | 238.7 | 258.6 |

20 | 1.7291 | 38.7 | 58.0 | 77.3 | 96.7 | 116.0 | 135.3 | 154.7 | 174.0 | 193.3 | 212.7 | 232.0 | 251.3 |

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## Share and Cite

**MDPI and ACS Style**

Matsushima, R.; Uchida, H.; Watanabe, R.; Oikawa, H.; Oogida, I.; Kosaka, Y.; Kanamori, M.; Akamine, T.; Suzuki, T.
Anatomical Distribution of Diarrhetic Shellfish Toxins (DSTs) in the Japanese Scallop *Patinopecten yessoensis* and Individual Variability in Scallops and *Mytilus edulis* Mussels: Statistical Considerations. *Toxins* **2018**, *10*, 395.
https://doi.org/10.3390/toxins10100395

**AMA Style**

Matsushima R, Uchida H, Watanabe R, Oikawa H, Oogida I, Kosaka Y, Kanamori M, Akamine T, Suzuki T.
Anatomical Distribution of Diarrhetic Shellfish Toxins (DSTs) in the Japanese Scallop *Patinopecten yessoensis* and Individual Variability in Scallops and *Mytilus edulis* Mussels: Statistical Considerations. *Toxins*. 2018; 10(10):395.
https://doi.org/10.3390/toxins10100395

**Chicago/Turabian Style**

Matsushima, Ryoji, Hajime Uchida, Ryuichi Watanabe, Hiroshi Oikawa, Izumi Oogida, Yuki Kosaka, Makoto Kanamori, Tatsuro Akamine, and Toshiyuki Suzuki.
2018. "Anatomical Distribution of Diarrhetic Shellfish Toxins (DSTs) in the Japanese Scallop *Patinopecten yessoensis* and Individual Variability in Scallops and *Mytilus edulis* Mussels: Statistical Considerations" *Toxins* 10, no. 10: 395.
https://doi.org/10.3390/toxins10100395